After a 50 per cent share-price jump over the past 12 months, Next has seen its rating downgraded by Credit Suisse from 'outperform' to 'neutral', causing the stock to fall on Friday morning.The broker has removed the shares from its 'Focus List' after the 37% outperformance of the benchmark FTSE 100 index.The stock was down 2.52% at 4,216p by 09:32 in morning trade.Credit Suisse said that some of the drivers of the financial year (ending January 2014) have not been quite as significant as expected: "The outlook for Homeware sales, Directory service enhancements and customer growth in 2H 2012/13 are all slightly behind where we hoped they would be at this stage of the year, providing slightly less confidence in forecasts."As such, it believes that there is little chance of upgrades to full-year numbers until the second half following a slow January and expected slow first quarter.Meanwhile, Next has given mixed messages on share repurchases, the broker said."The company has shown clear reluctance to buy back shares above £45, and has yet to pay over £43. We don't see a long-term alternative to buybacks, but for as long as it remains well behind its full-year run rate, the buyback question will be a cloud; both technically in terms of support, and potentially in terms of the earnings per share accretion for the next two years."Next's valuation - trading a 13.5 times forward earnings - is close to 10-year highs, Credit Suisse said.The target price has been lifted from 4,450p to 4,650p, which leaves just 6.0% upside to the current price.BC