pass1 - making usageList (24 chroms): 120 millis pass2 - checking and writing primary data (836694 records, 3 fields): 768 millis pass1 - making usageList (24 chroms): 53 millis pass2 - checking and writing primary data (371986 records, 3 fields): 357 millis pass1 - making usageList (24 chroms): 20 millis pass2 - checking and writing primary data (138709 records, 3 fields): 138 millis pass1 - making usageList (24 chroms): 10 millis pass2 - checking and writing primary data (72583 records, 3 fields): 83 millis