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12% of the money is suspected fraudulent, not the transactions, right? So could be that fraudulent transactions are a smaller volume of the total transactions, but they simply tend to be higher in terms of dollar amount.

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Fraud is typically very small dollar amounts used to test the card. Partially to try to go unnoticed but also to leave as much of the limit available as possible for intended purchases later.

Card testing doesn’t require a purchase, fraudsters can validate a card by adding it to an online wallet. The retailer will send a $0 authorization to the bank.

Fraud happens across all transaction amounts, what do you think people use the cards for once they buy or guess a valid card?

$0 authorizations are routinely skipped, though - the fees add up substantially because of card testing, some card networks don't support it (and instead you need $1 or similar), and it can be confusing for customers.

GP got it wrong. These are transaction counts, not $ totals.

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