transactionFeeDollarDemandPerYear = {
return users.map((userCount, idx) => {
if (idx) return Math.round((userCount - users[idx-1]) * percentageOfUsersTransacting * averageDollarValuePerTrade * numberOfTransactionsPerUserYear * transactionFee)
return userCount * percentageOfUsersTransacting * averageDollarValuePerTrade * numberOfTransactionsPerUserYear * transactionFee
})
}