Cost cutting and rate increases that took effect in Illinois and Missouri last year helped Ameren Corp. post an 11 percent increase in third-quarter profit.

Net income increased to $227 million, or $1.04 a share, compared with $204 million, or 97 cents a share, in the same period a year ago.

Revenue fell 12 percent to $1.82 billion as utility customers used less electricity because of cool summer weather and the recession, and profit margins on wholesale power sales declined.

Ameren utilities in Illinois got approval to raise electric and natural gas rates by $161 million in September 2007. In January, the Missouri Public Service Commission approved a $163 million electric rate increase for AmerenUE.

Excluding employee severance costs and other one-time expenses, Ameren earned $255 million, or $1.16 a share. The company earned $246 million, or $1.17 a share, on the same basis last year.