With the first-quarter 2016 earnings season in full swing, investors are keeping a close eye on the performance of the companies, especially given a stressed quarter in which market sentiments were weighed down by several issues including the slowdown of the Chinese economy, the continued volatility in commodity prices and global growth uncertainties.As of Apr 27, 2016, 209 members of the S&P 500 index, constituting 52.4% of the index’s total market capitalization, have come out with their results. Per our latest Earnings Preview article, total earnings for these 209 index members are down 5.5% on 1.6% lower revenues, on a year-over-year basis.Overall, this quarter is expected to witness an earnings decline in 9 of the 16 Zacks sectors. While the winners include Autos, Construction, Business Services and Medical, sectors including Basic Materials, Industrial Products, and Conglomerates do not look encouraging.Regarding the Finance sector, the picture is far from decent. About 54.5% of the companies have already reported their results. Total earnings for these companies decreased 5% on 4.2% lower revenues. However, the beat ratio seems strong with 64.6% surpassing bottom-line expectations and 56.3% beating on top line. Interestingly, given the downward trend in earnings estimate revisions prior to the earnings release, companies pulling an earnings surprise should not sound unusual.With several other index members set to release results, let’s find out what’s in store for these three finance sector companies that will report on Apr 29.Legg Mason Inc. LM: We expect the company to beat earnings expectations in fiscal fourth-quarter 2016. The company’s AUM for Mar 2016 was $669.6 billion, down from $702.7 billion in the prior-year period. Notably, the company experienced long-term outflows of $3.2 billion for March, resulting in $13.1 billion of outflows for the fiscal fourth-quarter. Despite the global uncertainties and market volatility that prevailed in the quarter, we believe Legg Mason’s diversified nature of business will boost its fiscal fourth-quarter results (read more: Legg Mason to Report Q4 Earnings: A Beat in Store?).Notably, the Baltimore-based global asset management firm surpassed earnings estimates in three of the trailing four quarters, with an average beat of 10.29%.Aon plc AON: The company provides risk management services, insurance and reinsurance brokerage, human resource consulting and outsourcing services worldwide. The company delivered an 8.61% positive surprise last quarter. Aon has an Earnings ESP of 0.00% and a Zacks Rank #3 (Hold). The Zacks Consensus Estimate for the quarter is pegged at $1.33.Aon should benefit from new business, strong retention rates, and returns on the company’s investments in industry leading data and analytics. However, unfavorable foreign currency translation, higher interest expense and heightened competition from insurers and reinsurers may weigh on the company’s performance (read more: Will Q1 Earnings Hold a Surprise for Aon Stock?).With respect to the surprise trend, Aon surpassed expectations in each of the last four quarters, with an average beat of 4.29%.Moody's Corporation MCO: The company’s business has been impacted by an increasing slowdown in issuance for high-yield bonds, as well as CMBS. Further, Moody’s faces significant economic risks tied with the volatile macro environment and its impact on the financial markets and soft bond issuance, which also results in sluggish demand for credit ratings.However, the company along with Standard & Poor’s, holds a dominant position in the duopolistic credit rating industry. It has also gained significant market share in the analytics business, which is not correlated with the volatility of interest rates and should add stability to the top line (read more: Moody's Q1 Earnings: What's in the Cards This Time?).Over the past four quarters, the company has posted an average positive earnings surprise of 5.72%.Stay tuned! Check back on our full write-up on earnings releases of these stocks.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report MOODYS CORP (MCO): Free Stock Analysis Report LEGG MASON INC (LM): Free Stock Analysis Report AON PLC (AON): Free Stock Analysis Report To read this article on Zacks.com click here.