Holdings gaps
[L=20.1965,33,96; 24.1969,57,70,95,123,246-247,260,299; 25.1970,41,66,74,83,99,101,131,177,188,191,229,257,268,293; 26.1971,26,29,85,125,132,133,305; 27.1972,19,200; 30.1975,16,235; 31.1976,84,148,248; 33.1978,39,121,126,153,220,221; 34.1979,1,178; 38.1984,299]