# Polar Ice Cores Annual 10Be Data for the Neutron Monitor Era #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # Template Version 4.0 # Encoding: UTF-8 # NOTE: Please cite original publication, NOAA Landing Page URL, dataset and publication DOIs (where available), # and date accessed when using these downloaded data. If there is no publication information, please cite investigator, study title, NOAA Landing Page URL, and date accessed. # # NOAA_Landing_Page: https://www.ncei.noaa.gov/access/paleo-search/study/13566 # Landing_Page_Description: NOAA Landing Page of this file's parent study, which includes all study metadata. # # Study_Level_JSON_Metadata: https://www.ncei.noaa.gov/pub/data/metadata/published/paleo/json/noaa-icecore-13566.json # Study_Level_JSON_Description: JSON metadata of this file's parent study, which includes all study metadata. # # Data_Type: Ice Cores # # Dataset_DOI: 10.25921/tdjc-0g67 # # Science_Keywords: #-------------------- # Resource_Links # # Data_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/icecore/antarctica/law/pedro2012bipolar10be-noaa.txt # Data_Download_Description: NOAA Template File; Composite 10Be Data # # Original_Source_URL: # Original_Source_Description: # #-------------------- # Contribution_Date # Date: 2012-11-07 #-------------------- # File_Last_Modified_Date # Date: 2022-09-21 #-------------------- # Title # Study_Name: Polar Ice Cores Annual 10Be Data for the Neutron Monitor Era #-------------------- # Investigators # Investigators: Pedro, J.B.(https://orcid.org/0000-0002-0728-2712); McConnell, J.R.(https://orcid.org/0000-0001-9051-5240); van Ommen, T.D.(https://orcid.org/0000-0002-2463-1718); Fink, D.(https://orcid.org/0000-0001-7156-4602); Curran, M.A.J.(https://orcid.org/0000-0003-1874-4086); Smith, A.M.; Simon, K.J.(https://orcid.org/0000-0003-4443-4305); Moy, A.D.(https://orcid.org/0000-0002-7664-9960); Das, S.B. #-------------------- # Description_Notes_and_Keywords # Description: Annually-resolved 10Be concentrations, stable water isotope ratios and accumulation rate data from the DSS site on Law Dome, East Antarctica (spanning 1936-2009) and the Das2 site, southeast Greenland (1936-2002). A composite record constructed from these records and previously published records from NGRIP, Renland, and Dye 3 (Greenland) and Dronning Maud Land (Antarctica) is also provided. # # References for DSS data spanning 2000-2010: Pedro et al. Clim. Past 7:707; Pedro et al. JGR 116:D23120. # Reference for the Dronning Maud Land (DML), Antarctica and Renland, Greenland records: Aldahan et al. 1996 # Reference for the Dye 3, Greenland data: Beer et al. 1984 # Reference for the NGRIP, Greenland data: Berggren et al. 2009 # # Note: All measurements are calibrated to the NIST SRM 4325 10Be standard reference material, utilising the Nishiizumi et al. (2007) 10Be:9Be ratio of (2.79 +/- 0.02) x 10^(-11) # # All normalization is relative to the 1951-1984 mean of the respective records. # Filtering refers to removal of data points exceeding 2 sigma from the respective mean. # The composite is an evenly weighted average of the normalized and filtered records at all time steps for which there is at least one Antarctic and one Greenland data point. #-------------------- # Publication # Authors: J.B. Pedro, J.R. McConnell, T.D. van Ommen, D. Fink, M.A.J. Curran, A.M. Smith, K.J. Simon, A.D. Moy, S.B. Das # Journal_Name: Earth and Planetary Science Letters # Published_Title: Solar and climate influences on icecore 10Be records from Antarctica and Greenland during the neutron monitor era # Published_Date_or_Year: 2012 # Volume: 355-356 # Pages: 174-186 # Issue: # Report_Number: # DOI: 10.1016/j.epsl.2012.08.038 # Full_Citation: # Abstract: Cosmogenic 10Be in polar ice cores is a primary proxy for past solar activity. However, interpretation of the 10Be record is hindered by limited understanding of the physical processes governing its atmospheric transport and deposition to the ice sheets. This issue is addressed by evaluating two accurately dated, annually resolved ice core 10Be records against modern solar activity observations and instrumental and reanalysis climate data. The cores are sampled from the DSS site on Law Dome, East Antarctica (spanning 1936-2009) and the Das2 site, southeast Greenland (1936-2002), permitting inter-hemispheric comparisons. Concentrations at both DSS and Das2 are significantly correlated to the 11-yr solar cycle modulation of cosmic ray intensity, rxy = 0.54 with 95% CI [0.31; 0.70], and rxy = 0.45 with 95% CI [0.22; 0.62], respectively. For both sites, if fluxes are used instead of concentrations then correlations with solar activity decrease. The strength and spectral coherence of the solar activity signal in 10Be is enhanced when ice core records are combined from both Antarctica and Greenland. The amplitudes of the 11-yr solar cycles in the 10Be data appear inconsistent with the view that the ice sheets receive only 10Be produced at polar latitudes. Significant climate signals detected in the 10Be series include the zonal wave three pattern of atmospheric circulation at DSS, rxy = -0.36 with 95% CI [-0.57; -0.10], and the North Atlantic Oscillation at Das2, rxy = -0.42 with 95% CI [-0.64; -0.15]. The sensitivity of 10Be concentrations to modes of atmospheric circulation advises caution in the use of 10Be records from single sites in solar forcing reconstructions. #-------------------- # Publication # Authors: J.B. Pedro, A.M. Smith, K.J. Simon, T.D. van Ommen, and M.A.J. Curran # Journal_Name: Climate of the Past # Published_Title: High-resolution records of the beryllium-10 solar activity proxy in ice from Law Dome, East Antarctica: measurement, reproducibility and principal trends # Published_Date_or_Year: 2011 # Volume: 7 # Pages: 707-721 # Issue: # Report_Number: # DOI: 10.5194/cp-7-707-2011 # Full_Citation: # Abstract: Three near-monthly resolution 10Be records are presented from the Dome Summit South (DSS) ice core site, Law Dome, East Antarctica. The chemical preparation and Accelerator Mass Spectrometer (AMS) measurement of these records is described. The reproducibility of 10Be records at DSS is assessed through intercomparison of the ice core data with data from two previously published and contemporaneous snow pits. We find generally good agreement between the five records, comparable to that observed between other trace chemical records from the site. This result allays concerns raised by a previous Antarctic study (Moraal et al., 2005) about poor reproducibility of ice core 10Be records. A single composite series is constructed from the three ice cores providing a monthly-resolved record of 10Be concentrations at DSS over the past decade (1999 to 2009). To our knowledge, this is the first published ice core data spanning the recent exceptional solar minimum of solar cycle 23. 10Be concentrations are significantly correlated to the cosmic ray flux recorded by the McMurdo neutron monitor (rxy = 0.64, with 95 % CI of 0.53 to 0.71), suggesting that solar modulation of the atmospheric production rate may explain up to ~40 % of the variance in 10Be concentrations at DSS. Sharp concentration peaks occur in most years during the summer-to-autumn, possibly caused by stratospheric incursions. Our results underscore the presence of both production and meteorological signals in ice core 10Be data. #-------------------- # Publication # Authors: Pedro, J.B., U.E. Heikkilä, A. Klekociuk, A.M. Smith, T.D. van Ommen, and M.A.J. Curran # Journal_Name: Journal of Geophysical Research: Atmospheres # Published_Title: Beryllium-10 transport to Antarctica: Results from seasonally resolved observations and modeling # Published_Date_or_Year: 2011 # Volume: 116 # Pages: # Issue: D23 # Report_Number: D23120 # DOI: 10.1029/2011JD016530 # Full_Citation: # Abstract: Cosmogenic 10Be measured in polar ice cores has important application in the reconstruction of past solar activity. However, the processes controlling its atmospheric transport and deposition to the ice sheets are not fully understood. Here we use the seasonal changes in 10Be concentrations in a 10 year monthly resolved ice core record from the Law Dome site (East Antarctica) in conjunction with ECHAM5-HAM general circulation model (GCM) simulations of 10Be and 7Be deposition as tools to examine this problem. Maximum 10Be concentrations are observed in the ice core during the austral late summer to early autumn (summer-autumn), while minimum concentrations are observed during the austral winter. The GCM simulations, corroborated by earlier observations of 10Be:7Be ratios in Antarctica from the Georg von Neumayer air sampling station, suggest that the 10Be concentration maximum is linked to direct input of stratospheric 10Be from the Antarctic stratosphere to the lower levels of the Antarctic troposphere during the austral summer-autumn. This result contrasts with the modeled transport of 10Be to Greenland, where the seasonal maximum in stratospheric input is seen in the late winter to spring, synchronous with the timing of the seasonal maximum in midlatitude stratosphere to troposphere exchange. Our results suggest that a different combination of processes is responsible for the transport of 10Be to the Antarctic and Greenland ice sheets. #-------------------- # Publication # Authors: Aldahan, A., G. Possnert, S. Johnsen, H. Clausen, E. Isaksson, W. Karlen, M. Hansson # Journal_Name: Proceedings of the Indian Academy of Sciences # Published_Title: Sixty year 10Be record from Greenland and Antarctica # Published_Date_or_Year: 1998 # Volume: 107 # Pages: 139-147 # Issue: 2 # Report_Number: # DOI: 10.1007/BF02840464 # Full_Citation: # Abstract: We report in this study the distribution of10Be in the top 40 m of the Renland ice core (East Greenland) and in a 30 m long core from DML (Dronning Maud Land, Antarctica) for the period 1931-1988. The two sites show differences in10Be content, the Antarctica site showing smaller variance and a lower average10Be annual flux. Similarly, the average accumulation rate (cm water equivalent year-1) is higher in the Renland relative to DML. The variability in accumulation (precipitation) rates seems to explain part of the difference in10Be flux between the two polar sites. Cyclic fluctuations of10Be flux correlate with the 11-year sunspot number and cosmic ray intensity than with the aa index (perturbation of the geomagnetic activity by the solar wind). Our data corroborate 10Be cyclic fluctuation pattern from the Dye 3 ice core and confirm a promising potential for correlation of global and local events. #-------------------- # Publication # Authors: Beer, J., H. Oeschger, M. Andrée, G. Bonani, M. Suter, W. Wölfli and C. C. Langway Jr. # Journal_Name: Annals of Glaciology # Published_Title: Temporal variations in the 10Be concentration levels found in the Dye 3 ice core, Greenland # Published_Date_or_Year: 1984 # Volume: 5 # Pages: 16-17 # Issue: # Report_Number: # DOI: 10.3189/1984AoG5-1-16-17 # Full_Citation: # Abstract: In order to study in some detail the variability of the 10Be concentration and its correlation with climatic parameters such as δ18O we have investigated 28 samples of the deep ice core from Dye 3, Greenland, covering the depth interval from 1 860 to 1 890 m which corresponds to the period 30 to 40 ka BP. The results show that the mean 10Be concentration during this period is higher by a factor of 1.7 than during the twentieth century and that there is a correlation between 10Be results and δ18O values. A possible explanation is that during cold periods (low δ18O values) precipitation rates are lower and therefore the number of 10Be atoms per gram of ice is higher. However, processes strongly related to δ18O values alone cannot explain the entire variability of the 10Be results. #-------------------- # Publication # Authors: Berggren, A.-M., J. Beer, G. Possnert, A. Aldahan, P. Kubik, M. Christl, S. J. Johnsen, J. Abreu, and B. M. Vinther # Journal_Name: Geophysical Research Letters # Published_Title: A 600-year annual 10Be record from the NGRIP ice core, Greenland # Published_Date_or_Year: 2009 # Volume: 36 # Pages: # Issue: # Report_Number: L11801 # DOI: 10.1029/2009GL038004 # Full_Citation: # Abstract: Despite the extensive use of 10Be as the most significant information source on past solar activity, there has been only one record (Dye-3, Greenland) providing annual resolution over several centuries. Here we report a new annual resolution 10Be record spanning the period 1389–1994 AD, measured in an ice core from the NGRIP site in Greenland. NGRIP and Dye-3 10Be exhibits similar long-term variability, although occasional short term differences between the two sites indicate that at least two high resolution 10Be records are needed to assess local variations and to confidently reconstruct past solar activity. A comparison with sunspot and neutron records confirms that ice core 10Be reflects solar Schwabe cycle variations, and continued 10Be variability suggests cyclic solar activity throughout the Maunder and Spörer grand solar activity minima. Recent 10Be values are low; however, they do not indicate unusually high recent solar activity compared to the last 600 years. #-------------------- # Publication # Authors: Pedro, J., van Ommen, T., Curran, M., Morgan, V., Smith, A., and McMorrow, A. # Journal_Name: Journal of Geophysical Research: Atmospheres # Published_Title: Evidence for climate modulation of the 10Be solar activity proxy # Published_Date_or_Year: 2006 # Volume: 111 # Pages: # Issue: D21 # Report_Number: D21105 # DOI: 10.1029/2005JD006764 # Full_Citation: # Abstract: We used a snow pit record in conjunction with detailed snow accumulation data and oxygen isotope records to examine atmospheric transport and deposition effects on 10Be at Law Dome, Antarctica. Data from an adjacent automatic weather station was used to date the record at snowfall event--scale resolution. In contrast to prior ice core studies in Antarctica, the snow pit record is of a sufficiently short duration (~1 year) that 10Be fluctuations reflect mainly atmospheric transport processes rather than solar modulation of production. Elevated concentrations of 10Be were found in the late austral summer and early autumn snow, synchronous with the seasonal increase in stratospheric aerosols at Antarctic stations. A significant (P < 0.01) anticorrelation of 10Be with d18O occurs at the snowfall event scale. Fractionation of water isotopes at Law Dome is controlled by local and regional processes, specifically transport and local temperature. The anticorrelation seen here implies that 10Be concentration was reduced in snow from warmer air masses (characterized by less negative d18O). There is potential for confounding solar modulation with climatic modulation if at sites such as this one, warmer meteorological influences may be associated with reduced 10Be concentrations. Quantification of the significance of this effect for the longer-term 10Be record will require analysis of longer 10Be records from different sites. #-------------------- # Funding_Agency # Funding_Agency_Name: Australian Institute of Nuclear Science and Engineering Research (AINSE) # Grant_Number: #-------------------- # Funding_Agency # Funding_Agency_Name: Australian Nuclear Science and Technology Organisation (ANSTO) # Grant_Number: ICCAS #-------------------- # Funding_Agency # Funding_Agency_Name: Australian Antarctic Division # Grant_Number: AAS#2384, AAS#3064 and AAS#1172 #-------------------- # Funding_Agency # Funding_Agency_Name: Australian Cooperative Research Centres Programme # Grant_Number: ACE CRC #-------------------- # Site_Information # Site_Name: Greenland and Antarctic Composite # Location: Polar # Northernmost_Latitude: 75.1 # Southernmost_Latitude: -73.6 # Easternmost_Longitude: 112.8 # Westernmost_Longitude: -43.82 # Elevation: #-------------------- # Data_Collection # Collection_Name: 2012bipolar10Be # First_Year: 1935 # Last_Year: 2009 # Time_Unit: CE # Core_Length: # Parameter_Keywords: radiogenic isotopes # Notes: All normalisation is relative to the 1951-1984 mean of the respective records. Filtering refers to removal of data points exceeding 2 sigma from the respective mean. The composite is an evenly weighted average of the normalised and filtered records at all time steps for which there is at least one Antarctic and one Greenland data point. Full details in Pedro et al., EPSL, 2012. #-------------------- # Chronology_Information # Chronology: # # # #------------------ # Variables # # PaST_Thesaurus_Download_Resource: https://www.ncdc.noaa.gov/paleo/skos/past-thesaurus.rdf # PaST_Thesaurus_Download_Description: Paleoenvironmental Standard Terms (PaST) Thesaurus terms, definitions, and relationships in SKOS format. # # variables format: shortname what,material,error,units,seasonality,data_type,detail,method, C(har) or N(umeric) data,additional information # ## age_AD ice age,,,year Common Era,,ice cores,,,N,Mid-date ## 10be_DSS 10Be,bulk ice,,count per gram,,ice cores,,accelerator mass spectrometry,N,10E4 atoms/gram; Law Dome DSS ## 10be_Das2 10Be,bulk ice,,count per gram,,ice cores,,accelerator mass spectrometry,N,10E4 atoms/gram; Greenland Das2 ## 10be_Dye3 10Be,bulk ice,,count per gram,,ice cores,,accelerator mass spectrometry,N,10E4 atoms/gram; Greenland Dye3 ## 10be_NGRIP 10Be,bulk ice,,count per gram,,ice cores,,accelerator mass spectrometry,N,10E4 atoms/gram; NGRIP ## 10be_Ren 10Be,bulk ice,,count per gram,,ice cores,,accelerator mass spectrometry,N,10E4 atoms/gram; Renland ## 10be_DML 10Be,bulk ice,,count per gram,,ice cores,,accelerator mass spectrometry,N,10E4 atoms/gram; Dronning Maud Land ## 10be-norm_DSS 10Be,bulk ice,,mu unit,,ice cores,normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; Law Dome DSS ## 10be-norm_Das2 10Be,bulk ice,,mu unit,,ice cores,normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; Greenland Das2 ## 10be-norm_Dye3 10Be,bulk ice,,mu unit,,ice cores,normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; Greenland Dye3 ## 10be-norm_NGRIP 10Be,bulk ice,,mu unit,,ice cores,normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; NGRIP ## 10be-norm_Ren 10Be,bulk ice,,mu unit,,ice cores,normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; Renland ## 10be-norm_DML 10Be,bulk ice,,mu unit,,ice cores,normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; Dronning Maud Land ## 10be-normfilt_DSS 10Be,bulk ice,,mu unit,,ice cores,filtered;normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; removed data points exceeding 2 sigma from the mean; Law Dome DSS ## 10be-normfilt_Das2 10Be,bulk ice,,mu unit,,ice cores,filtered;normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; removed data points exceeding 2 sigma from the mean; Greenland Das2 ## 10be-normfilt_Dye3 10Be,bulk ice,,mu unit,,ice cores,filtered;normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; removed data points exceeding 2 sigma from the mean; Greenland Dye3 ## 10be-normfilt_NGRIP 10Be,bulk ice,,mu unit,,ice cores,filtered;normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; removed data points exceeding 2 sigma from the mean; NGRIP ## 10be-normfilt_Ren 10Be,bulk ice,,mu unit,,ice cores,filtered;normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; removed data points exceeding 2 sigma from the mean; Renland ## 10be-normfilt_DML 10Be,bulk ice,,mu unit,,ice cores,filtered;normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; removed data points exceeding 2 sigma from the mean; Dronning Maud Land ## 10be-norm_comp 10Be,bulk ice,,mu unit,,ice cores,composited;filtered;normalized,accelerator mass spectrometry,N,mu units relative to the 1951-1984 mean; evenly weighted average of the normalised and filtered records at all time steps for which there is at least one Antarctic and one Greenland data point ## 10be-err_comp 10Be,bulk ice,one standard error,mu unit,,ice cores,filtered;normalized,accelerator mass spectrometry,N,standard error of composite #-------------------- # Data: # Missing_Values: NA age_AD 10be_DSS 10be_Das2 10be_Dye3 10be_NGRIP 10be_Ren 10be_DML 10be-norm_DSS 10be-norm_Das2 10be-norm_Dye3 10be-norm_NGRIP 10be-norm_Ren 10be-norm_DML 10be-normfilt_DSS 10be-normfilt_Das2 10be-normfilt_Dye3 10be-normfilt_NGRIP 10be-normfilt_Ren 10be-normfilt_DML 10be-norm_comp 10be-err_comp 1935.50 1.11 1.60 1.50 1.66 1.18 1.24 1.66 1.18 1.24 1.36 0.15 1936.50 0.79 0.56 0.70 1.46 0.89 1.26 0.92 1.05 0.97 0.66 1.26 0.92 1.05 0.97 0.66 0.97 0.10 1937.50 0.70 0.51 0.67 1.37 1.50 1.40 1.10 0.83 1.00 0.91 1.11 1.16 1.10 0.83 1.00 0.91 1.11 1.16 1.02 0.05 1938.50 0.66 0.69 1.01 1.32 1.50 0.81 1.04 1.13 1.51 0.87 1.11 0.67 1.04 1.13 1.51 0.87 1.11 0.67 1.06 0.11 1939.50 0.68 0.44 0.51 0.93 0.91 1.30 1.08 0.72 0.76 0.62 0.67 1.08 1.08 0.72 0.76 0.62 0.67 1.08 0.82 0.08 1940.50 0.70 0.48 0.56 1.31 1.20 1.20 1.11 0.80 0.84 0.87 0.88 1.00 1.11 0.80 0.84 0.87 0.88 1.00 0.92 0.05 1941.50 0.64 0.51 0.65 1.19 0.70 1.02 0.84 0.97 0.79 0.52 1.02 0.84 0.97 0.79 0.52 0.83 0.09 1942.50 0.73 0.48 0.89 1.01 1.30 1.15 0.79 1.33 0.67 0.96 1.15 0.79 1.33 0.67 0.96 0.98 0.12 1943.50 0.71 0.64 1.11 1.63 1.30 2.90 1.13 1.06 1.66 1.08 0.96 2.41 1.13 1.06 1.66 1.08 0.96 1.18 0.12 1944.50 0.58 0.68 0.57 1.65 1.10 0.92 1.11 0.85 1.10 0.81 0.92 1.11 0.85 1.10 0.81 0.96 0.06 1945.50 0.66 0.66 0.63 1.33 1.10 1.05 1.08 0.94 0.89 0.81 1.05 1.08 0.94 0.89 0.81 0.96 0.05 1946.50 0.71 0.53 0.67 1.12 1.10 1.13 0.88 1.00 0.74 0.81 1.13 0.88 1.00 0.74 0.81 0.91 0.07 1947.50 0.63 0.48 0.57 1.10 0.91 1.00 0.79 0.85 0.73 0.67 1.00 0.79 0.85 0.73 0.67 0.81 0.06 1948.50 0.60 0.52 0.92 1.16 1.00 1.30 0.95 0.85 1.38 0.77 0.74 1.08 0.95 0.85 1.38 0.77 0.74 1.08 0.96 0.10 1949.50 0.66 0.53 0.63 1.46 1.40 1.05 0.87 0.94 0.97 1.16 1.05 0.87 0.94 0.97 1.16 1.00 0.05 1950.50 0.68 0.57 1.17 1.02 1.40 2.20 1.07 0.94 1.75 0.68 1.03 1.83 1.07 0.94 0.68 1.03 0.93 0.09 1951.50 0.77 0.51 1.03 2.42 1.70 1.30 1.23 0.83 1.54 1.61 1.25 1.08 1.23 0.83 1.54 1.25 1.08 1.19 0.12 1952.50 0.80 0.50 1.01 1.50 1.30 1.40 1.27 0.82 1.51 0.99 0.96 1.16 1.27 0.82 1.51 0.99 0.96 1.16 1.12 0.10 1953.50 0.74 0.58 1.24 1.46 1.50 1.30 1.18 0.95 1.85 0.97 1.11 1.08 1.18 0.95 0.97 1.11 1.08 1.06 0.04 1954.50 0.74 0.49 0.76 1.26 1.50 1.17 0.80 1.14 0.84 1.24 1.17 0.80 1.14 0.84 1.24 1.04 0.09 1955.50 0.70 0.73 1.01 1.36 1.60 1.60 1.10 1.20 1.51 0.90 1.18 1.33 1.10 1.20 1.51 0.90 1.18 1.33 1.20 0.08 1956.50 0.65 0.82 0.56 1.40 1.70 1.03 1.34 0.84 0.93 1.25 1.03 1.34 0.84 0.93 1.25 1.08 0.10 1957.50 0.57 0.52 0.90 1.60 2.00 0.84 0.90 0.85 1.35 1.07 1.47 0.70 0.90 0.85 1.35 1.07 1.47 0.70 1.06 0.12 1958.50 0.51 0.46 0.40 0.99 0.00 0.69 0.81 0.76 0.60 0.66 0.57 0.81 0.76 0.60 0.66 0.57 0.68 0.05 1959.50 0.49 0.43 0.48 1.23 1.90 1.30 0.78 0.71 0.72 0.82 1.40 1.08 0.78 0.71 0.72 0.82 1.40 1.08 0.92 0.11 1960.50 0.52 0.38 0.41 1.25 1.20 1.20 0.83 0.62 0.61 0.83 0.88 1.00 0.83 0.62 0.61 0.83 0.88 1.00 0.79 0.06 1961.50 0.56 0.58 0.40 1.05 0.98 0.79 0.88 0.96 0.60 0.70 0.72 0.66 0.88 0.96 0.60 0.70 0.72 0.66 0.75 0.06 1962.50 0.63 0.59 0.49 1.66 1.90 0.91 0.99 0.98 0.73 1.11 1.40 0.76 0.99 0.98 0.73 1.11 1.40 0.76 0.99 0.10 1963.50 0.69 0.73 0.64 2.09 1.80 1.30 1.10 1.20 0.96 1.39 1.33 1.08 1.10 1.20 0.96 1.39 1.33 1.08 1.18 0.07 1964.50 0.75 0.94 0.69 1.05 2.10 1.30 1.18 1.54 1.03 0.70 1.55 1.08 1.18 1.03 0.70 1.55 1.08 1.11 0.14 1965.50 0.90 0.88 1.05 3.21 2.00 1.20 1.42 1.45 1.57 2.13 1.47 1.00 1.45 1.57 1.47 1.00 1.37 0.13 1966.50 0.81 0.88 0.61 1.74 1.90 1.60 1.29 1.45 0.91 1.15 1.40 1.33 1.29 1.45 0.91 1.15 1.40 1.33 1.26 0.08 1967.50 0.61 0.71 0.85 1.69 2.00 1.20 0.97 1.16 1.27 1.12 1.47 1.00 0.97 1.16 1.27 1.12 1.47 1.00 1.17 0.08 1968.50 0.67 0.90 0.46 1.44 1.70 1.50 1.07 1.48 0.69 0.96 1.25 1.24 1.07 0.69 0.96 1.25 1.24 1.04 0.10 1969.50 0.69 0.54 0.49 1.14 1.10 0.96 1.09 0.88 0.73 0.76 0.81 0.80 1.09 0.88 0.73 0.76 0.81 0.80 0.84 0.05 1970.50 0.57 0.61 0.41 1.03 1.00 0.84 0.90 1.00 0.61 0.68 0.74 0.70 0.90 1.00 0.61 0.68 0.74 0.70 0.77 0.06 1971.50 0.49 0.53 0.50 1.35 1.70 0.84 0.77 0.88 0.75 0.90 1.25 0.70 0.77 0.88 0.75 0.90 1.25 0.70 0.87 0.08 1972.50 0.60 0.45 0.35 1.77 0.95 0.89 0.95 0.75 0.52 1.17 0.70 0.74 0.95 0.75 0.52 1.17 0.70 0.74 0.81 0.09 1973.50 0.66 0.55 0.69 1.61 1.80 1.40 1.04 0.90 1.03 1.07 1.33 1.16 1.04 0.90 1.03 1.07 1.33 1.16 1.09 0.06 1974.50 0.72 0.47 1.00 1.47 1.10 1.40 1.15 0.78 1.50 0.98 0.81 1.16 1.15 0.78 1.50 0.98 0.81 1.16 1.06 0.11 1975.50 0.76 0.58 0.59 1.31 1.20 1.50 1.20 0.96 0.88 0.87 0.88 1.24 1.20 0.96 0.88 0.87 0.88 1.24 1.01 0.07 1976.50 0.68 0.50 0.57 1.38 1.10 1.50 1.09 0.82 0.85 0.91 0.81 1.24 1.09 0.82 0.85 0.91 0.81 1.24 0.95 0.07 1977.50 0.68 0.69 0.64 1.85 1.20 1.20 1.07 1.14 0.96 1.23 0.88 1.00 1.07 1.14 0.96 1.23 0.88 1.00 1.05 0.05 1978.50 0.57 0.66 0.62 1.37 0.00 0.77 0.91 1.09 0.93 0.91 0.64 0.91 1.09 0.93 0.91 0.64 0.90 0.07 1979.50 0.55 0.55 0.61 1.58 1.10 1.50 0.88 0.91 0.91 1.05 0.81 1.24 0.88 0.91 0.91 1.05 0.81 1.24 0.97 0.06 1980.50 0.62 0.55 0.65 0.96 0.39 1.50 0.99 0.90 0.97 0.64 0.29 1.24 0.99 0.90 0.97 0.64 0.29 1.24 0.84 0.14 1981.50 0.58 0.55 0.66 1.28 1.20 1.40 0.93 0.91 0.99 0.85 0.88 1.16 0.93 0.91 0.99 0.85 0.88 1.16 0.95 0.05 1982.50 0.45 0.61 1.01 1.48 0.80 0.84 0.71 1.01 1.51 0.98 0.59 0.70 0.71 1.01 1.51 0.98 0.59 0.70 0.92 0.14 1983.50 0.36 0.64 0.49 1.71 1.50 1.10 0.58 1.05 0.73 1.14 1.11 0.91 1.05 0.73 1.14 1.11 0.91 0.99 0.07 1984.50 0.35 0.56 0.46 1.50 1.20 0.55 0.91 0.69 1.00 1.00 0.91 0.69 1.00 1.00 0.90 0.07 1985.50 0.32 0.64 2.18 1.40 1.60 0.50 1.06 1.45 1.03 1.33 1.06 1.45 1.03 1.33 1.22 0.10 1986.50 0.34 0.47 1.46 1.10 0.55 0.78 0.97 0.91 0.78 0.97 0.91 0.89 0.06 1987.50 0.35 0.60 1.11 1.10 0.55 0.98 0.74 0.91 0.98 0.74 0.91 0.88 0.07 1988.50 0.37 0.78 1.65 1.00 0.59 1.28 1.10 0.83 1.28 1.10 0.83 1.07 0.13 1989.50 0.37 0.42 1.41 0.59 0.69 0.94 0.69 0.94 0.81 0.13 1990.50 0.46 0.45 0.85 0.73 0.74 0.57 0.73 0.74 0.57 0.68 0.06 1991.50 0.48 0.44 1.11 0.76 0.73 0.74 0.76 0.73 0.74 0.74 0.01 1992.50 0.51 0.57 1.52 0.82 0.93 1.01 0.82 0.93 1.01 0.92 0.06 1993.50 0.65 0.68 1.49 1.03 1.11 0.99 1.03 1.11 0.99 1.04 0.04 1994.50 0.65 0.59 1.60 1.04 0.98 1.06 1.04 0.98 1.06 1.03 0.02 1995.50 0.63 0.84 0.99 1.39 0.99 1.39 1.19 0.20 1996.50 0.58 0.69 0.92 1.14 0.92 1.14 1.03 0.11 1997.50 0.61 0.65 0.96 1.07 0.96 1.07 1.02 0.06 1998.50 0.59 0.74 0.94 1.21 0.94 1.21 1.07 0.14 1999.50 0.41 0.45 0.65 0.74 0.65 0.74 0.69 0.04 2000.50 0.54 0.53 0.86 0.87 0.86 0.87 0.87 0.00 2001.50 0.38 0.59 0.60 0.98 0.98 2002.50 0.44 0.53 0.70 0.87 0.70 0.87 0.79 0.08 2003.50 0.46 0.74 0.74 2004.50 0.46 0.74 0.74 2005.50 0.73 1.16 1.16 2006.50 0.79 1.26 1.26 2007.50 0.84 1.33 1.33 2008.50 0.74 1.17 1.17 2009.50 0.67 1.06 1.06