BRATISLAVA, Slovakia — When Jozef Lazarcik, a 35-year-old factory worker, heard his number called on national television here recently, he pumped his fists, hardly believing his luck.

He had registered only nine receipts with Slovakia’s new tax lottery, and yet he had just won a new car. “It’s a heavenly feeling,” he said before leaving the studio, ready to encourage all of his friends to register their receipts, too — which is exactly what Slovakian officials were hoping for.

Over the last 10 years, Slovakia’s revenue from value-added taxes, a type of sales tax, has declined. But hiring auditors and pursuing individual merchants and service providers in court is expensive and slow. So last fall, the government decided to put a lottery in the mix.

The idea is to enlist average citizens to collect receipts from their purchases and register them with the government, creating a paper trail for transactions and forcing restaurant and shop owners to pay the sales taxes they owe. As Slovakians register their receipts for the lottery, a computer will also tell them if a merchant has issued a receipt with a fake tax identification number, so they can report suspected fraud.