Riot Blockchain (RIOT) stock jumps 5.7% in premarket trading after reporting it produced 187 bitcoin (BTC-USD) in March 2021, an 80% increase from its pre-halving March 2020 production of 104 BTC.In Q1 2021, RIOT produced 491 bitcoin, up 7% vs. pre-halving Q1 2020 production of 281 bitcoin; as of March 31, Riot holds more than 1,565 bitcoin on its balance sheet, all of which were produced by its mining operations.Bitcoin gains 1.5%, trading recently at ~$60.5K, up 78% in the past three months.Riot's stock gains have far outpaced bitcoin's in the past six months as seen in chart below.Last week, Riot announced contracts to add 42,000 more S19j Antminers for $138.5M.