A lot of companies in the financial sector took a pretty serious beating over the last five years. The housing bubble acted like a tidal wave that sunk all ships in the financial sector, and life insurance companies, which are often heavily invested in the market, didn't escape it. However, some five years later, it may be time for investors to rethink companies in the financial sector that had previously been overlooked. With the economy appearing to be in recovery, there's a chance that a buying opportunity could exist for stocks that show bullish valuations despite a rocky recent history.

These five life insurance stocks all have prices that appear relatively low based on their book value, sales, growth projections, and earnings. This could easily be because all of these companies, save one, is down over 20 percent over the last five years with the fall starting during the financial crisis. While predicting broad economic trends is never a sure thing, the fact that these companies appear to be a bargain buy at their current price might make them an attractive investment going forward.

Each of these following stocks met the following criteria for this screen. A market cap over $300 million, P/E of under 12.50, a forward P/E under 7.75, a PEG under one, a P/S under 0.75, and a P/B under one. Taken cummulatively, these all point to a share price that might not be in line with the underlying value of these companies. (If you're wondering what all these things mean, here's a quick refresher.)

Metlife (MET)

Market Cap: $40.79 billion   P/E: 6.15   Forward P/E: 6.91   PEG: 0.64   P/S: 0.58   P/B: 0.68

It's endorsed by Snoopy, what else could really matter? Metlife is an industry giant and well known brand name, and after losing about 40 percent of its share price over the last five years it could be a good time to get in.

Prudential Financial (PRU)

Market Cap: $28.75 billion   P/E: 8.37   Forward P/E: 7.49   PEG: 0.71   P/S: 0.59   P/B: 0.78

Prudential is another leader of the industry, boasting an array of financial products and services to its clients. Down over 30 percent over the last five years, it could be available at a bargain price.

Reinsurance Group of America (RGA)

Market Cap: $4.23 billion   P/E: 12.35   Forward P/E: 7.57   PEG: 0.78   P/S: 0.61   P/B: 0.69

Reinsurance Group of America is a holding company that, through its subsidiaries, engages in the life and health insurance industries. This is, however, the only company that came out of the financial crisis relatively unscathed, gaining just over 8.5 percent during the period in question.

Protective Life Corp. (PL)

Market Cap: $2.27 billion   P/E: 7.08   Forward P/E: 7.51   PEG: 0.89   P/S: 0.70   P/B: 0.54

Protective Life is another holding company that sells financial products through its subsidiaries like Protective Life Insurance Company. Since the start of March in 2007, the company's lost almost 40 percent of the value of its stock.

Symetra Financial Corporation (SYA)

Market Cap: $1.18 billion   P/E: 6.50   Forward P/E: 6.95   PEG: 0.71   P/S: 0.61   P/B: 0.44

Symetra is another financial services company in the life insurance industry. The loss of 22 percent of its share value over the last five years is relatively modest compared to some of the other companies on this list, but it's hardly unsubstantial.

*All data from finviz.com