Contributed by A.J. Crayon
Analysis of Messier Marathons, Observer Scope Average (as of April 27, 2015)


      number   |  Averages |
Year  scopes     in      mm
1781     1       3.5     89
1977     3       7.3    186
1978     1      10.0    254
1979     6       8.2    208
1980     8      12.0    304
1981    16       8.3    211
1982     7       9.6    245
1983    12       9.0    229
1984     5      12.2    310
1985    17      10.7    272
1986     2       6.0    152
1988     7      11.3    287
1989     1       8.0    203
1990     3      11.0    280
1991     1      13.1    333
1992     1      12.5    318
1993    15       8.7    221
1994    19       8.6    218
1995    29       9.4    240
1996    35       9.7    247
1997    23       9.8    250
1998     8       8.0    203
1999    41      11.4    289
2000    33       8.9    226
2001    80      14.2    361
2002    38       9.2    234
2003    76      11.4    291
2004    37       9.7    246
2005    55      10.1    256
2006    66       8.8    223
2007    86      11.6    294
2008    61       9.7    246
2009    57       9.3    236
2010    47       9.2    234
2011    35       9.1    231
2012    48       9.4    238
2013    34      10.3    261
2014    39       8.2    210
2015    35       9.6    245


Author: A.J. Crayon
http://messier.seds.org/xtra/marathon/Obs_scope_average-2015.txt