Buyers ran into a wall in mid-March and I think it is due to concern that earnings reports won't be as upbeat as in past quarters. Market adjusting to comfort level.
Economic reports are good, not great, but good, Look for the market to find a comfort level where it discounts uncertainty about earnings reports to be released shortly.
Without uncertainty out of Europe, our stock market would sizzle. May anyhow. Euro-situation due for catharsis and flow of money out of safe bonds into stocks.
Another breakthrough in Europe as Germany and France read Greece the riot act on its ill timed referendum. Investors welcomed the news with buying at the open.