I explain why the size of a Community fund participation in an SNS can be lower than the amount specified in the SNS proposal.
Determining the size of participation of the Community fund
As per the design of the Community fund (CF), the size of the participation in a particular SNS is determined as follows.
The CF participation amount, let’s call it X, is part of the SNS proposal. At the time of the proposal submission, the amount X is converted to a relative number determined via the calculation r% = X/(total amount of maturity available in the CF). The idea is that each CF neuron participates with a proportion r% of its maturity.
Adjustment for changes in the CF size
If CF neurons opt out of the CF whilst an SNS proposal is open for voting, then the ICP amount the CF was proposed to make is reduced proportionally. If neurons opt in when an SNS proposal is open for voting, the ICP amount the CF invests in an SNS remains the same, but each CF neuron will participate with less maturity (proportionally decreased).
Checking for maximum and minimum participation
When the SNS proposal is approved, for each CF neuron, r% of its maturity is compared against the maximum and minimum participation amount. If r%*maturity is above the maximum participation amount, the participation amount of that CF neuron is capped at the maximum participation amount. If r%*maturity is below the minimum participation amount, that CF neuron is excluded. In both cases the overall CF participation is reduced.
The SNS proposal of OpenChat specified a CF amount of 333’333 ICP. The total amount available in the CF was 3.4M, when the proposal was submitted and when it was approved. Thus the relative expected contribution from each CF neuron is approximately 9.8% = 333’333/3.4M.
Checking in the SNS launchpad today (just before the start of the sale on March 3rd around 8am CET), you can observe that the actual CF participation is only 333’173.01 ICP.
Thus, the actual CF participation is a tiny bit lower, namely by an amount 159.99 ICP, compared to the originally requested amount. Given that the size of the CF did not change during the proposal voting, this effect must be due to CF neurons which are capped (because they have too much maturity) or excluded (because they have too little maturity).