hm, in the video Todd Combs mentioned listening to Buffett say to do this in 2001. Its likely you start seeing massive benefits of this within 5 years. So overall at least 20 years ago, but most likely started much earlier.
Also Elon Musk is mostly self-taught through reading: http://qr.ae/3PHgP
Also Elon Musk is mostly self-taught through reading: http://qr.ae/3PHgP