Adam Back, a Bitcoin infrastructure developer, wrote in a post: "In my opinion, if we move from a gradual transition to a sudden phase, the addition of new users will intensify the adoption effect, invalidating the'diminishing return 'halving theory and reaching the top of the S-curve, just as Bitcoin pioneer and first BTC recipient Hal Finney (@halfin) estimated the $200 trillion addressable market in January 2009, Bitcoin's S-curve may now enter a steeper period." "My guess is that the trend of diminishing returns could break upward in the next two to five years," added Back.