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*** Delta C-13 values (per mil) derived from CO2 in flask air      ***
*** samples collected at Shetland Islands, Scotland                ***
*** Source: C. E. Allison                                          ***
***              R. J. Francey                                     ***
***              P. B. Krummel                                     ***  
***              Atmospheric, Research, Commonwealth Scientific,   ***
***              And Industrial Research Organisation,             ***
***              Aspendale, Victoria,                              *** 
***              Australia  3195                                   ***                   
***                                                                ***   
*** September 2003                                                 ***
***                                                                ***
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	Jan.	Feb.	Mar.	Apr.	May	Jun.	Jul.	Aug.	Sep.	Oct.	Nov.	Dec.	Ann. Ave.

1992												-8.113	
1993	-8.066	-8.045	-8.132	-8.173	-8.169	-8.045	-7.65	-7.393	-7.498	-7.712	-7.915	-8.068	-7.906
1994	-8.136	-8.143	-8.198	-8.214	-8.147	-8.02	-7.734	-7.487	-7.543	-7.812	-8.002	-8.082	-7.960
1995	-8.163	-8.192	-8.223	-8.263	-8.245	-8.063	-7.737	-7.578	-7.695	-7.886	-8.011	-8.126	-8.015
1996	-8.227	-8.232	-8.233	-8.246	-8.231	-8.134	-7.81	-7.509	-7.576	-7.825	-8.016	-8.152	-8.016
1997	-8.202	-8.19	-8.244	-8.379	-8.372	-8.124	-7.767	-7.547	-7.708	-7.981	-8.083	-8.17	-8.064
1998	-8.277	-8.299	-8.338	-8.341	-8.278	-8.156	-7.802	-7.58	-7.766	-8.008	-8.13	-8.239	-8.101
1999	-8.349	-8.362	-8.363	-8.395	-8.367	-8.224	-7.906	-7.672	-7.785	-7.982	-8.112	-8.22	-8.145
2000	-8.287	-8.32	-8.353	-8.359	-8.315	-8.212	-7.943	-7.654	-7.683	-7.897	-8.121	-8.278	-8.119
2001	-8.321	-8.351	-8.395	-8.403	-8.341	-8.191	-7.896	-7.641	-7.721	-7.962	-8.137	-8.26	-8.135


Monthly values (per mil) are reported on the international VPDB-CO2 scale. Monthly values were 
calculated as the mean of the daily values from a smooth curve fit to the data using the curve-
fitting routines described by Thoning et al., 1989 (J. Geophys Res. 94, 8549-8565).  Annual 
values are the arithmetic means of the 12 monthly values.