LINCOLN, Neb. (AP) — A new report says special interests spent more than $15.6 million last year trying to influence Nebraska state government officials.

The group Common Cause Nebraska said in its annual report Tuesday that the total is the largest amount ever spent on lobbying. Total compensation for lobbyists increased to $14.5 million in 2015, compared to $13 million the previous year. Money spent on entertainment and gifts reached a new high of more than $396,000.

Last year also saw an increase in the number of groups that hire lobbyists, to a record-high 545.

Jack Gould, the group’s issues chairman, says lawmakers should be compensated through an increased salary to minimize the role that lobbyists play. State senators make $12,000 a year and receive a per diem.