This is how we calculate Total Hits. I think it is fairly close to RAW, and if it isn't, it's how our RAW is set
Total Concussion Hits = Base Hits [CO/10 rounded up + hits rolled per rank (up to racial maximum)] * (1+CO Bonus/100) + (ProfLevelBonus * Ranks)
Example: 4th level Dwarven Fighter with 90 CO (+25 bonus) and 10 ranks in Body Development (with an average of 6 rolled per rank), would have: 90/100 (9) + 6*10 (60) => 69 Base Hits, 69 * (1 + 25/100) = 86.25 rounds down to 86 + 3*4 (12) => 98 total hits.
Example 2: Same Dwarven Fighter at 10th level and 22 ranks in Body Development (with an average of 6 rolled per rank), would have: 90/100 (9) + 6*22 (132) => 141 Base Hits (over max racial, so capped at 120), 120 * (1 + 25/100) = 150 + 3*22 (66) => 216 total hits.