.... which is, patek has made in total numbers, far greater than the total numbers of patek 1518 + 2499 all put together. Not trying to shoot you down, your math calculation is fine, no doubt.
Just assume all your numbers are correct ... personally, i think there is far more patek 5970P than what people might think. Have you ever consider, that just maybe, patek 5970J is the least number in production ?
I am sure, your children and grand children will marvel at your watch collection by 2067. Time will preserve the value of your time piece, along with inflation, will give you a pretty good return but ONLY if it is sold.
i do thank You for your illustration, Patek 5970P is indeed a cool piece.