1390 and pass rate

Look at this trend since they lowered it to 1390 (with the exception of Oct. 2020)… See how Feb. remains lower than 40%; July remains lower than 60%. How come there is no drastic change in the pass rate when in fact they already lowered the cut score up to 50 points? 50 freaking points! I encourage that along with the audit of the F25, they also audit why the pass rate remains very low despite the cut score already being lowered by 50 points! Thank you.