Omnicom Group (NYSE:OMC) communicated better-than-expected second-quarter results this morning. But with shares down around 2% Tuesday as of this writing, it appears the market isn't impressed.

To be sure, at first glance the results don't look particularly strong; revenue fell 1.7% year over year to $3.81 billion, which translated to a 5.9% increase in net income per share to $1.26. But analysts' models were less optimistic, with consensus estimates calling for lower revenue of $3.76 billion, and earnings of just $1.22 per share.

The primary culprit behind Omnicom's top-line decline was a 7.1% negative impact from foreign exchange -- a temporary consequence of operating a global business -- offset partially by a 0.1% increase in revenue from acquisitions and organic growth of 5.3%. Within the latter, organic revenue from advertising increased 6.4%, CRM climbed 4.3%, public relations rose 0.3%, and specialty communications jumped 8%.

On a geographical basis, organic revenue declined 9.6% in the smaller Latin American market, but rose in all other regions, including growth of 5.9% in the core North American market, 5.4% in the U.K., 3.9% in Europe, 7.6% in Asia Pacific, and 11.9% in Africa and the Middle East. When all was said and done, North America continued to play its usual outsized role in propping up Omnicom's overall results:

Omnicom Geographical

Omnicom 2015 revenue by region, Credit: Omnicom Group

That revenue translated to a 1.5% decline in adjusted earnings before interest, taxes, and amortization of intangibles (EBITA) to $565.7 million, and a 3.5% drop in net income to $313.9 million. To Omnicom's credit, however, keep in mind that last year's second quarter included an income tax benefit of $11 million related to its failed $35 billion merger with Publicis. Excluding this one-time item, net income would have fallen only marginally on a year-over-year basis. 

Omnicom has also generated healthy free cash flow of $756.8 million year to date, which helps fund its ongoing dividend and stock repurchase efforts and, consequently, drives the increase in net income per share. Through the first six months of 2015, Omnicom has already paid over $311 million in dividends ($61.1 million to noncontrolling interest shareholders), and repurchased more than $386 million in stock net of proceeds and excess tax benefits from stock plans.

In addition, Omnicom showed some serious efficiency allocating capital under its control. Return on invested capital rose to 17.6% for the 12 months ended June 30, 2015, up from 16.9% the previous year, and return on equity climbed to an enormous 35.9%, up from 31.5% for the year ended June 30, 2014.

Omnicom also extended its streak of returning over 100% of net income to shareholders through dividends and share repurchases since 2004, lending credence to its status as a solid play for long-term investors seeking dividend growth and otherwise aggressive capital returns:

Omnicom Shareholder Cash Returned

Credit: Omnicom Group

Even so, during the subsequent conference call management underscored investors' worries about today's uncertain advertising environment, saying that a record number of media accounts are under review. Omnicom Group CEO John Wren elaborated:

We know the media landscape has become more complex, and many of the reviews are strategic reevaluations of agency suppliers. Technology has radically changed media planning and buying. The rise of digital data and analytics has given marketers the ability to more precisely understand how consumers are using media. In areas such as programmatic buying and micro-targeting, clients want to make sure that they have the right partner with the right resources in the space.

To his credit, Wren also insisted Omnicom remains "especially well positioned as a result of our investments in Annalect and our data management platform."  

Annalect is a digital data and analytics group launched by Omnicom with this very purpose in mind almost five years ago. As it stands, Wren noted Omnicom is roughly halfway through its agency pitches for the largest assignments, and this process should largely be complete by the end of October. Given this uncertainty -- and despite Omnicom's strong quarterly results relative to Wall Street's expectations -- I wouldn't be the least bit surprised if the market's caution persists for the time being.

Steve Symington has no position in any stocks mentioned. The Motley Fool recommends Omnicom Group. Try any of our Foolish newsletter services free for 30 days. We Fools may not 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.