Bestandslücken
[N=1977,21,31,34,41-42,45-46;1978,8-10,12-15,17,19,23,28,35,41;1979,7,9,11,15,24,37-38;1980,1,5,8-9,11,13,15-19,23-24,26,31-33,36-37,40-42,44-45,48-49;1981,24;1982,7,27-28,32,49-50;1983,15-18,30,37-38,42,45;1984,17-18,29-30,36-37,49-50;1985,2,26-29,31-32,39-40;1990,48;1992,49;1993,26,30-33,44]