There's hardly any certainty in the market, but even I have to admit it's become almost comical that the Nasdaq Composite has hit a new high (including intraday highs) in 17 straight sessions while the broad-based S&P 500 (SNPINDEX:^GSPC) has now risen 19 consecutive Tuesdays. It's an odd pattern, but certainly one that's allowed traders to build upon this year's incredible gains.

Today, yet again, without a lack of important economic data, leadership from some of the nation's biggest companies helped drive the S&P 500 higher. Particularly, home-improvement retail chain Home Depot (NYSE:HD) jumped nearly 3% after reporting better-than-expected first-quarter results and raising its full-year outlook. Home Depot finds itself in the sweet spot with commercial construction rebounding and many homeowners still well underwater in their homes and looking to remodel. It's certainly a company you can trust moving forward.

For the day, the S&P 500 finished higher by 2.87 points (0.17%) to close at 1,669.16, another new record. In spite of the tame move, three S&P 500 components had monstrous moves higher today.

Medical-device maker Medtronic (NYSE:MDT) led the pack higher today, tacking on 4.9% after reporting its fourth-quarter results. Skeptics had been concerned with the impact of the medical-device excise tax heading into this report, but Medtronic silenced them with continued steady growth. For the quarter, sales rose by 4% to $4.46 billion as adjusted EPS rose to $1.10. Comparatively, the Street was expecting just $1.03 in EPS on $4.38 billion in revenue. International sales were the big key for Medtronic, with its all-important pacemaker and defibrillator line of products seeing sales rise by 3%. Furthermore, emerging-market revenue rose by 14% on a constant currency basis for the quarter. As long as Medtronic continues to exploit strength in burgeoning growth markets, this will remain a solid investment over the long run.

Shares of drugmaker Merck (NYSE:MRK) also vaulted higher by 4.7% following a presentation at the UBS Global Healthcare Conference yesterday. Clearly, investors and analysts alike are happy with what they heard from Merck and are encouraged by the pharmaceutical giant's pipeline. However, as Foolish health-care analyst Max Macaluso points out, Merck's pipeline isn't without its uncertainties. As Max notes, the company's insomnia drug Suvorexant certainly isn't a lock for approval when it goes before the Food and Drug Administration later this summer.

Finally, auto-parts retailer AutoZone (NYSE:AZO) put the pedal to the metal and advanced 4.6% following the release of its third-quarter results. For the quarter, net sales increased 4.5% to $2.2 billion as EPS rose at a much faster 16% clip. AutoZone attributed the better results to a rougher winter, which helped its replacement-parts business. However, I remain decidedly pessimistic on AutoZone at these levels. Comparable-store sales actually saw a 0.1% decline, and the company has been fueling EPS growth primarily through share buybacks instead of actual growth. AutoZone is carrying an insane amount of debt on its books that seems to rise with each passing quarter and could threaten to put the company in a bind if it ever falls into a rough growth patch. 

Fool contributor Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

The Motley Fool owns shares of Medtronic and recommends Home Depot. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.