I think this is going to be a difficult question to give a concrete answer to. (For many reasons: data isn’t public, growth is very lumpy)
Probably the best approximation I can think of would be betting volumes in equivalent events over time.
US Presidential elections matched volumes on Betfair (in £): * 2008: ~15mm (Source) * 2012: ~40mm (Source) * 2016: ~200mm (Source) * 2020: ~1700mm (~600mm pre-event which is possibly more relevant)
That’s a ~40x over 12 years, or ~35%/year.
We’ll get another data point after the French Election this year and I guess it would be interesting to look at some other comparable events. (UK General Elections).
Another place we could look at is volumes on PredictIt, although that’s really just a proxy for number of markets. You could also look at volumes on Polymarket or one of the other crypto exchanges.
The prediction market after the event was ~ a betting market on “Will the election results be upheld?” rather than “Who will win the election on election night?”. We were comparing those markets to similar markets earlier (“who will win” markets) rather than “Will election results be overturned?”
I think this is going to be a difficult question to give a concrete answer to. (For many reasons: data isn’t public, growth is very lumpy)
Probably the best approximation I can think of would be betting volumes in equivalent events over time.
US Presidential elections matched volumes on Betfair (in £):
* 2008: ~15mm (Source)
* 2012: ~40mm (Source)
* 2016: ~200mm (Source)
* 2020: ~1700mm (~600mm pre-event which is possibly more relevant)
That’s a ~40x over 12 years, or ~35%/year.
We’ll get another data point after the French Election this year and I guess it would be interesting to look at some other comparable events. (UK General Elections).
Another place we could look at is volumes on PredictIt, although that’s really just a proxy for number of markets. You could also look at volumes on Polymarket or one of the other crypto exchanges.
Thanks!!! Why is the pre-event more relevant?
The prediction market after the event was ~ a betting market on “Will the election results be upheld?” rather than “Who will win the election on election night?”. We were comparing those markets to similar markets earlier (“who will win” markets) rather than “Will election results be overturned?”
There is a new CFTC-regulated prediction market to add to this list: https://kalshi.com/.