Premium income at the nation's five major nonlife insurance firms fell 4.1 percent in fiscal 1998 from the previous year due to premium rate cuts and sluggish sales amid the recession, according to earnings reports released Thursday.

All five firms logged a decline in premium income, which totaled 3.76 trillion yen. The firms cited the lackluster economy and recent cuts in auto insurance premiums as factors that pushed down revenue.

Many firms have moved to slash their auto insurance premiums since rate liberalization last July. Deregulation has also opened doors to foreign insurers and new entrants from nonfinancial sectors such as Sony Corp. and H.I.S. Co., further heating up competition.