WATCH: More work but fewer resources reason for tax delays, says IRS Commissioner

The Internal Revenue Service is responsible for more work but has been given fewer resources to do it, causing delays in responses, IRS Commissioner Charles Rettig said before the House Subcommittee on Government Operations on Thursday.

Watch the hearing in the player above.

“The IRS is serving more people and entities in a global environment than ever before, while handling new and bigger responsibilities,” Rettig said in his prepared remarks.

READ MORE: The IRS is still working through last year’s backlog. Here’s what to know about your taxes this year

He said the lack of resources include the IT system which has not been updated, leaving paper documentation still used throughout the organization.

“This use of paper processes can result in significant delays, contributing to IRS inventories and limiting taxpayers’ ability to know the status of their cases,” said Rettig.

Rettig said that, when adjusted for inflation, the IRS’ budget had dropped by 15 percent in the past 10 years and last year had a $100 million budget hole that had to be plugged.

“We are left depleting resources from one less-visible program to pay for another essential program, which causes us to slow or stop work on updates to our systems that must be modernized to provide digital services that citizens expect from us,” Rettig said.

According the the subcommittee website, the IRS faces a backlog of 23 million pieces of correspondence from the 2021 tax season and has a long history of staff shortages thanks in part to budget cuts totaling $929 million from 2014 to 2019. The IRS workforce has been reduced by a fifth since 2010.