VICTORIA - British Columbia's auditor general says the provincial government needs to know more about the billions of dollars in tax breaks it gives to people and corporations every year.

Carol Bellringer says the government's reporting of tax expenditures and how they relate to government spending has been largely unchanged for the past 25 years.

She says the province must ensure politicians have all the information they need to decide whether tax expenditures, estimated at $7 billion in 2016-2017, help achieve their objectives.

The tax breaks give support to social, economic and environmental policy objectives but Bellringer says providing those benefits comes at a cost of lost revenues.

For example, she says the government doesn't charge provincial sales tax on the purchase of new bicycles to help meet its environmental goals, but that means it gives up about $23 million in taxes every year.

Bellringer says B.C.'s homeowner grant, introduced in 1957 to relieve the pressure of rising property taxes, is a decades old expenditure that has undergone few changes or reviews since its introduction.