Semiconductor stocks are still broadly in the green for the last year.

For semiconductors stocks, it's another case of the Mondays.

The Philadelphia Semiconductor Index SOX index reversed earlier gains in Monday afternoon trading to turn sharply lower following another weak earnings report from a major chipmaker stock. The index traded lower 1.25% by the market close Monday. The index has shed about 9.2% of its value in the last three months.

Source: Yahoo Finance
Source: Yahoo Finance

Monday's weakness came as ams AG (AUKUF) , an $8.3 billion European manufacturer, reported earnings the fell significantly short of Wall Street's estimates. Austria-based ams said it forecasts negative operating margins at around negative 20% to negative 25% given underutilization of product capacity throughout its facilities in Singapore.

After ams reported the shortfall, the SOX index dipped to about 1% above its 200-day moving average. Among the worst performers on the index are Micron Technology Inc. (MU - Get Report) , down 3.16% Monday, Skyworks Solutions Inc. (SWKS - Get Report) , down 2.79%, and Analog Devices Inc. (ADI - Get Report) , down 1.97%.

Losses this week would compound weakness that began last week in semiconductors. The SOX index is lower nearly 6% in the last five trading sessions and has declined in the last four-straight trading days. Despite recent weakness, the index remains higher 24% in the last year.

Texas Instruments Inc. (TXN - Get Report) and Teradyne Inc. (TER - Get Report) are the next major semiconductor stocks to report, with financials expected after the closing bell on Tuesday, April 24.