CHICAGO (CBS) — The city brought in a lot less money from the new disposable bag tax than expected in its first year, but officials said that’s because people are bringing reusable bags to the grocery, and there’s less litter as a result.

The 7-cent tax on paper and plastic bags at grocery stores and other businesses was expected to bring $9.2 million after it went into effect in February, but Budget & Management office spokeswoman Molly Poppe said a lot more shoppers than expected are using their own bags.

“We’ve seen over a 40 percent reduction in disposable bag use since the implementation of the bag tax, and we did not actually expect something that high in the first year, so that’s why you see our revenue for 2018 actually reflect $5 million in revenue instead of the $9.2 [million],” she said.

Poppe said fewer disposable bags means less litter and landfill.

While bag tax revenue was less than expected this year, Poppe said the ground transportation tax has brought in approximately $41 million more than expected, mostly because of the surge in ride-hailing services like Uber and Lyft.

“What we’re actually seeing is we’re going to receive about $109 million in ground transportation tax revenue in 2018, and that’s up by about $41 million in growth over what we actually initially projected,” she said.

The city also will be getting less from the state for at least one other tax, but Poppe said the city can handle all the fluctuations.