Gross gaming yield (GGY) from B2 machines in Great Britain fell 18% year-on-year to £1.5bn ($1.89bn) for the period October 2017 to September 2018.
Figures released by the Gambling Commission showed the average number of B2 machines also fell by a marginal 1% to 33,190, not matching the accompanying fall in GGY.
FOBT maximum stakes were reduced from £100 to £2 on 1 April 2019.
However, the new limitation came into effect after the reported period, not accounting for the significant dip in B2 revenue.
By contrast, off course B3 machine revenue rose astronomically from £1.9m to £323.1m, making up for the reduced FOBT revenue within betting shops.
On a broader scale, total GGY grew 4% within the British gambling industry, to £14.5bn, while remote GGY increased 17% to £5.6bn.
This means online betting now holds a 39% market share of all gambling in Great Britain; a 4% year-on-year rise.
The total number of betting shops in Great Britain fell by 2% to 8,423 from March 2018 (no data is available for October 2017).