Editor's note: As part of our partnership with Nightly Business Report, TheStreet's Jill Malandrino of OptionsProfits will join NBR Monday (check local listings) to look at stock ideas that represent outperformance in the market.As the market continues its slow grind upward, institutional traders and retail investors alike question the rally on lack of trading volume. From the retail perspective, many long-term investors are disenchanted with the market place, in general, following confidence fails with Principal Financial Group ( PFG), Knight ( KCG) and name brand recognition IPOs such as Facebook ( FB) and Groupon ( GRPN). Are they worrying too much? Yes, it is true that share volume has trended lower since late 2008, breaking a multiple decade trend of expanded trading activity. Michael Santoli of Barron's pointed out that this could merely be a partial give-back from the huge tripling of volume from 2004-09. And it makes complete sense. Think about it. A big part of this can be attributed to the explosion of high-frequency trading (HFT) and, obviously, the financial crisis. I also correlate it to what we have seen in China -- a sort of give back in growth data following a surge in her economy in just the past decade alone. It may not be as much of a slowdown, but more of an indication of true demand. Another reason for lower volume is the CBOE Volatility Index (VIX) is at the low end of a five-year range. It does not necessarily mean fear is out of the market or investors are complacent. On a more technical level, a big part of it is the way the VIX is structured and due to timing cycles. But one thing for sure is traders expect volatility to pop in September and October based on trading in VIX and futures markets and that is a big contributing factor as to why volume is lower now in addition to the traditional summer slowdown. So it's not related to investors breaking out the party hats, it's due to no new money coming to market. Have investors missed out, yet again, on participating in the upward trend? Absolutely not. There are plenty of companies that have proven their worth in a tough macro environment that boast healthy balance sheets and continue to reward investors. As always, diversifying across multiple sectors and investment style is key. So, let's put on our trading caps and take a look at two longer-term buys in two very different sectors.