“…Variable fees (f) are the payments charged by the bank per transaction. Whereas usually in theory this payment is non-negative in Russia it is negative since the issuing banks usually offer cardholders some forms of stimulating programs (e.g., bonuses, cashback) for making payments by card (Chernikova, Faizova, Egorova, & Kozhevnikova, 2015;Chizhikova, 2013;Krivosheya & Korolev, 2016). Fixed fees (F) are the payments for card issuance and service, which are independent of the number of transactions (for example, annual service fees) (Baxter, 1983;Bedre-Defolie & Calvano, 2013;Krivosheya & Korolev, 2016).…”