MAYFIELD VILLAGE, Ohio -- The insurer Progressive Corp. said Thursday that its second-quarter profit tumbled 52 percent, pulled down by investment losses.

The drop was more than Wall Street expected and Progressive shares fell more than 5 percent in midday trading.

The Mayfield Village, Ohio-based insurance company said its net income fell to $118.6 million, or 19 cents per share, in the three months ended June 30 from $245.2 million, or 38 cents per share, in the same quarter last year.

Analysts, on average, expected earnings of 27 cents per share, according to a FactSet poll.

Progressive posted a pretax loss on securities of $4.7 million compared with a gain of $26 million in the year-ago period.

Net premiums written during the period, a measure of the value of all new and renewal policies sold during the period, rose 8 percent to $4.13 billion. Net premiums earned, the portion of the premiums it earns when policies expire, rose 7 percent to $4 billion.

Progressive shares fell 94 cents, or 4.6 percent, to $19.61 in morning trading. Its shares have fallen 16 percent since peaking for the past year at $23.41 in early April.