TCountIf(a;b;c;d) counts how many times in the results a to b are greater than or equal to c but less than or equal to d, where c and d are times entered as seconds.
e.g. TCountIf(21;25;25200;36000) - Counts the number of times in Result IDs 21 - 25 which are greater than or equal to 25200s (07:00:00) and less than or equal to 36000 (10:00:00)