pass1 - making usageList (24 chroms): 99 millis pass2 - checking and writing primary data (692485 records, 3 fields): 613 millis pass1 - making usageList (24 chroms): 60 millis pass2 - checking and writing primary data (414762 records, 3 fields): 378 millis pass1 - making usageList (24 chroms): 32 millis pass2 - checking and writing primary data (218341 records, 3 fields): 211 millis pass1 - making usageList (24 chroms): 39 millis pass2 - checking and writing primary data (138117 records, 3 fields): 174 millis