The stock market may either be significantly overvalued, or it may be selling near historically low levels — it all depends on whom you’re talking to and what valuation metric they’re using. And in his latest column for Canada’s Globe and Mail, Validea CEO John Reese says that means investors shouldn’t rely on one single measure of value when making decisions.

“I believe strongly in using cold, hard data when investing,” Reese writes. “The problem is that any single piece of data can lie. That’s why it’s so important to consider a variety of information. You might say that, when it comes to the numbers, there is safety in numbers.”

Reese says investors can use several different metrics used to evaluate individual stocks to also gauge the valuation of the broader market. He examines several such measures. Among them: the stock market/GDP ratio and the price/sales ratio, both of which put the market in fair value territory, and the 10-year price/earnings ratio, which puts it in overvalued territory. To see all of the metrics and get John’s take on what they mean collectively for the market, click here.