Clomid statistics

Why is it so hard to find information about clomid statistics? I cannot find anything about percentage rate of overall pregnancy for couples. Does anyone have further insite to this? I understand there are varying factors to the statistics Ex; low sperm count, notovulatory or under lying medical issues. Fortunately all of these are negative for me (or seem to be). I’ve been ttc #2 for 4+ years now. I finally started taking clomid this cycle.