Following are the 1996 ultras with >50 starters:

Date                                 Start Fin
----------------------------------------------
11/23/96 JFK 50M                       690 625
 4/ 6/96 American River 50M            541 488
12/14/96 Sunmart Texas Trail 50K       476 438
 5/18/96 Ice Age 50M                   428 208
 6/29/96 Western States 100M           375 227
 3/16/96 Cool Canyon Crawl 50K         373 360
 8/24/96 Leadville 100M                320 150
12/14/96 Sunmart Texas Trail 50M       308 270
11/30/96 Quadruple Dipsea 28.4M        235 197
 8/ 4/96 Skyline 50K                   199 189
 8/24/96 Pt. Reyes 50K                 197 189
 7/20/96 Vermont 100M                  195 145
 3/23/96 Crown King Scramble 50K         ? 186
 6/ 1/96 Shadow of the Giants 50K      162 153
 9/14/95 IAU 24HR                      155 143
 4/20/96 Bull Run Run 50M              155 121
 3/23/96 Hinte-Anderson 50K            146 110
 9/ 7/96 Wasatch 100M                  146  92
10/19/96 Mountain Masochist 50M        145 119
 1/20/96 Jed Smith 50K                   ? 134
12/ 8/96 High Desert 50K               143 131
 4/20/96 Leona Divide 50M              141 125
 9/28/96 Angeles Crest 100M            140  96
 3/24/96 San Juan Trail 50K            139 126
 7/13/96 Knee Knackering 30M           137 125
 1/ 6/96 Avalon 50M                    129 110
 4/20/96 Trail Mix 50K                 115  99
10/ 6/96 VASS Trail 50M                112  93
10/12/96 Arkansas Traveler 100M        111  73
10/ 6/96 Vermont 50M                   110  94
 9/14/96 Bulldog 50K                     ? 106
10/ 5/96 Cuyamaca-Laguna 50K           107  99
 6/29/96 Fans 24 hr                      ?  99
10/26/96 Sierra Nevada 52.4M           106  90
 8/10/96 Howl at the Moon 8HR          102  85
 7/27/96 Minnesota Yoyageur Trail 50M  100  88
10/12/96 Firetrails 50M                 98  87
 6/ 7/96 Kettle Moraine 100M            95  63
 5/11/96 Quicksilver 50K                95  89
 7/12/96 Hardrock 100M                  91  43
 9/ 7/96 Baldy Peaks 50K                 ?  85
 4/27/96 Collegiate Peaks 50M           86  76
 5/11/95 Lost Boys 50M                  85  69
 9/28/96 Cle Elum Ridge 50K             82  79
10/12/96 Le Grizz 50M                    ?  73
 7/ 6/96 Swan Creek Crawl 50K           78  72
 4/27/96 California 50M                 77  70
 6/15/96 Holiday Lake 50K               77  69
 7/27/96 White River 50M                77  61
 5/ 4/96 Strolling Jim 40M              76  74
 5/19/96 Ohlone Wilderness 50K          75  74
 7/20/96 Elkhorn 100K                   74  69
 9/ 1/96 Run on the Sly 50K             73  71
10/ 6/96 Glacial Trail Run 50K           ?  70
 1/20/96 Mountain Mist 50K              72  68
 5/ 4/96 Massanutten Mt. 100M           72  37
 5/ 4/96 What, Mi'Wok? 100K             71  62
 5/18/96 Silver State 50K               70  66
 6/15/96 Mohican Trail 100M             70  32
 7/13/96 Rattlesnake Trail 50K          69  68
10/19/96 Mule Run 50K                    ?  61
 8/31/96 Groundhog 50M                  67  59
 9/21/96 Superior Trail 100M            67  44
 7/ 6/96 Afton Trail 50K                66  61
 5/ 5/96 McDonald Forest 50K            65  61
 9/ 1/96 Run on the Sly 50M             64  53
 2/24/96 Pueblo Nuevo 50M               63  44
11/ 9/96 San Juan Trail 50M             63  39
 5/11/96 Quicksilver 50M                60  42
 6/ 1/96 Old Dominion 100M              61  38
 7/ 6/96 Finger Lakes 50K                ?  57
10/19/96 Ed Fitzgerald 100K              ?  55
 6/15/96 Bighorn Mt. 52M                59  55
 9/28/96 Croom Trail 50K                58  54
 3/10/96 Knickerbocker 60K              57  57
 2/ 3/96 Rocky Racoon 100M              54  36
 6/15/96 Joe Kleinerman 12HR            53  48
 3/30/96 Chuckanut Mt. 50K              52  46
 5/ 4/96 Cornbelt 24HR                   ?  51
 8/17/96 Cameron Park 50M               51  42
10/19/96 Rocky Racoon Trail#1 50K       50  47

"http://reality.sgi.com/stanj/Freebies/largest"
 (updated: 2/28/97)