If it looks and sounds like a bull . . .

HISTORY says that standard bull markets typically last less than four years.

So, when the bull that sprang to life in March 2009 turned three this month, it understandably raised some concerns. Yet some Wall Street strategists mark the calendar differently. They contend that the bull market that began in 2009 actually ended last year, when the S&P 500 Index hit a rough patch from April to October.

During that stretch, the S&P 500 lost 19.4 per cent from peak to trough based on daily closing prices just shy of the 20 per cent threshold for a bear market. On October 3, though, the index actually fell through that barrier for a brief moment during the trading day.

If that was indeed a bear, the thinking goes, then a new bull market must have been born on October 3. And that would imply not only that stocks have more room to run, but also that sectors like technology, which are sensitive to shifts in the economic cycle, are likely to do well. Despite a slight downturn last week, they have been buoyant for months.

"From an official standpoint, the bull market is entering its fourth year because the market didn't officially decline by 20 per cent based on closing values," says Sam Stovall, chief equity strategist for S&P Capital IQ. "However, in terms of performance, I think the market will act as if we're in the first year of a new bull."

At the moment, it is. Historically, the first years of major rallies provide investors with the biggest boost the S&P 500 has posted gains of 38 per cent, on average, in year one of every past bull market since World War II. True to form, the rally that began on October 3 has already pushed the index 27 per cent higher in less than six months.

That surge isn't the only evidence supporting the view that Wall Street is in a new bull market. Normally, shares of small companies considered higher- risk but higher-returning assets than blue-chip stocks tend to outperform the broad market at the start of a new rally. Shares of large, industry-leading companies, by contrast, usually catch fire only after bull markets mature.

Sure enough, small-company stocks have been performing even better than the S&P 500 over the past six months. For instance, the Nasdaq Composite Index, made up of younger and faster-growing companies than are found in the S&P 500, is up more than 31 per cent since October 3, while the Russell 2000 Index of small stocks has gained 36 per cent.

At the same time, economically sensitive sectors like technology and consumer discretionary stocks have been outpacing the broad market since October, which is also typical of the first years of bull markets, Stovall notes.

He added that if this were the fourth year of an ageing bull, defensive areas of the market such as healthcare, consumer staples and utilities stocks would be leading the charge. Yet they haven't been.

Jason Hsu, chief investment officer for investment consulting firm Research Affiliates, says that even if investors are not convinced that this is the start of a new bull, market psychology is likely to keep pushing the markets higher for now.

"Research on short-term momentum in asset prices says that if you have had a strong six months of steady asset appreciation, that tends to drive further price appreciation," he said.

He added that many investors "did not participate in the fairly speculative, risk-asset rally that began in October." So, given the occasional herd mentality on Wall Street, these investors could simply be waiting for an opening to jump in.

As a result, Hsu says, he thinks the broad market could keep rallying in the short run, and that there could be continuing demand for riskier, economically sensitive stocks, especially on market dips.

To be sure, there are different types of bull markets so-called cyclical bulls that tend to run alongside a single economic expansion, as well as so-called secular bull markets that may last for more than a decade, often containing shorter bull and bear cycles within them. The sharemarket's epic run from 1982 to 1999, for instance, was the last big example of a secular bull.

"I don't think we've begun a new secular bull," says Mark Luschini, chief investment strategist at Janney Montgomery Scott. He points out that historically, secular bulls tend to start at price-to-earnings ratios in the single digits, as was the case in 1982. But based on valuations using 10-year average profits, the market's price-to-earnings ratio is above 20 times.

Doug Ramsey, chief investment officer at the Leuthold Group, also says that while this may be a new bull market, it is what he calls a "non-economic" rally.

In other words, this bull market unlike the one that began in March 2009 emerged after a bear market that did not coincide with an official recession.

What's the significance of that? "Recessions are what clear the decks for a longer-lasting recovery and drive valuations down to truly low levels from which bigger gains can spring," he said.

Ramsey's research on non-economic bull markets since World War II found that these rallies tend to be shorter lived they last on average just 31 months. And they tend to be more muted. While the typical non-economic bull market returned less than 62 per cent, cumulatively, the median bull market that emerged after recessions gained nearly 102 per cent.

Of course, given that stocks have gained 27 per cent so far in their current rally, that would still leave the market ample room for gains. NEW YORK TIMES