pass1 - making usageList (24 chroms): 178 millis pass2 - checking and writing primary data (1251764 records, 3 fields): 1097 millis pass1 - making usageList (24 chroms): 87 millis pass2 - checking and writing primary data (620776 records, 3 fields): 569 millis pass1 - making usageList (24 chroms): 30 millis pass2 - checking and writing primary data (234127 records, 3 fields): 224 millis pass1 - making usageList (24 chroms): 16 millis pass2 - checking and writing primary data (120719 records, 3 fields): 116 millis