Request predictions! How low will USMS records go by 2070?

I am writing a story for Swimmer magazine on where USMS records are likely to be 50 years from now and would truly appreciate your help in predicting these! There are a total of 1800+ individual pool records possible, so to narrow things down, I'm concentrating on two events in two age groups: the 100 yards free and the 400 yard IM in age groups 45-49 and 65-69. The current records here are pretty amazing, and the curves showing the trajectories since USMS began 50 years ago suggest there is likely plenty of room to drop. If you could send me your email address to jamesthornton1@comcast.net , I will send you my little prediction form plus graphs of the record trends. Thanks in advance. Alternatively, you could just post your predictions here. In any event, I need to have my story in by the 15th, so please act with some alacrity! Again, thanks so much in advance. PS if you could include any rationale behind your predictions (mathematical analysis, guess work, gut feeling, whatever) that would be fantastic! Note: current records and record holders are in red below. Name: _______________________ Your predictions for records by 2070: Men 100 Free Now:45-49 (N. Grainger: 46.21) 65-69 (R. Abrahams: 49.42) By 2070 _________________ _________________ Women 100 Free Now: 45-49 (E. Braun: 51.99) 65-69 (L. Val: 57.88) By 2070: _______________ _________________ Men 400 IM Now:45-49 (N. Grainger: 4:01.32) 65-69 (R. Colella: 4:30.64) By 2070: ___________ _____________________ Women 400 IM Now: 45-49 (K. Pipes-Nielsen: 4:32.87) 5-69 (L. Val: 5:21.70) By 2070: ___________ __________________ Rationale for your choices: