20th Century Doubles 2nd-Quarter Earnings

20th Century Industries, a Woodland Hills insurance company, said its second-quarter profit more than doubled from a year ago to $14.1 million, or 55 cents a share, from $6.9 million, or 29 cents a share.

Net investment income climbed to $10.2 million from $7.3 million a year earlier, while gross income from premium payments increased to $128.3 million from $100.7 million, said 20th Century, which provides auto and home insurance in California only.

The company said first-half 1987 profit rose to $22.6 million, or 88 cents a share, from $13.7 million, or 60 cents a share.