Hey Rick,
I've donated blood pretty much every 8-10 weeks as well for many years. Over the last year my blood tests revealed I have a low iron level. MCV 77 scale is 79-97, MCH is 25.2 scale is 26.6-33.0, RDW 17.2 scale 12.3-15.4. All other blood levels are fine. You have any issues arise with low iron from donating often?