Tech groups and insurance companies were out of favour on Monday afternoon, after sharp falls for ARM Holdings and Admiral weighed on their respective categories.Chip designer ARM Holdings was under pressure today after Deutshe Bank downgraded its rating on the stock from 'hold' to 'sell' and reduced its target price from 465p to 400p."Despite reflecting many of ARM's long-term growth drivers such as rising royalty rates and penetration of new markets in our model, we expect ARM's [earnings per share] growth to slow down to mid-teens," said analyst Kai Korschelt."Coupled with higher market share uncertainty and chip ASP erosion in mobile, we believe the stock can de-rate over time and downgrade from 'hold' to 'sell'."Meanwhile, in an interview with The Financial Times at the weekend, The group's Chief Executive Warren East said that the firm was cutting back of recruitment this year as it expects a slowdown in sales in the second half.Car insurance giant Admiral also fell after Credit Suisse downgraded its rating on the shares from 'outperform' to 'neutral' and reduced its target price from 1,300p to 1,250p, saying that there isn't much upside left in the stock. "Despite reporting a solid headline result and outlining multiple areas where buffers have been built to support future results, weaker-than-expected vehicle count growth, heightened pressure on industry pricing and larger-than-expected international losses have prompted us to lower earnings forecasts by 4-7% for FY12-14e," the broker said. Canaccord Genuity also downgraded Admiral to 'sell' today, while Exane BNP Paribas reiterated its 'underperform' recommendation. Top performing sectors so far todayHousehold Goods & Home Construction 7,425.83 +1.79%Fixed Line Telecommunications 2,607.89 +1.58%Industrial Metals & Mining 2,381.24 +1.51%Beverages 12,825.29 +1.32%Electronic & Electrical Equipment 3,350.26 +1.18%Bottom performing sectors so far todayTechnology Hardware & Equipment 770.92 -1.74%Insurance (non-life) 1,566.87 -0.43%