The volatility of the market has picked up quite a bit lately as U.S. stocks have stumbled three days in a row.  The earnings announcement of Hewlett-Packard Company (HPQ) certainly contributed, to some degree, to the today's market actions.  In fact, HP was forced to release its results early following a leaked memo from chief executive Leo Apotheker, which warned of "another tough quarter" from the company.  Investors who have positions or interest in HP were following closely to find out the results of the company's earnings.  The earnings release disappointed everyone combined with the additional drama of the leaked memo.  Ultimately, the stock closed down -7.26% for the day.  Walmart (WMT), Dell (DELL), and Home Depot (HD) are some of the other major companies that have also released earnings today although their earnings did not affect the performance of their stock's significantly.

If you think that your ETF portfolios are not affected during earnings season, you may want to think again as we were able to pull several ETFs that have significant weightings to some of those companies that have recently or are scheduled to report earnings.  For example, tomorrow, May 18, Deere (DE) is announcing its earnings, which has an 8.35% weighting in Market Vectors Agribusiness (MOO).  Another ETF that could potentially be impacted due to earnings is the iShares S&P GSTI Software Index (IGV), because two of its holdings are releasing earnings on Thursday, which are Intuit and Salesforce.com.  Their combined holdings add up to close to 13%.  Please refer to the list below for largely followed companies that are scheduled to have earnings coming out in the next several days.