LONDON -- The FTSE 100 (INDEX: ^FTSE) had been on the way up again, having beaten the 5,900-point barrier early in the week. But the post-election U.S. market drop, coupled with a weakening European economic outlook, sent it crashing, to end the week 99 points (1.7%) down at 5,770 points.

There were some big individual movers during the week too, but most of the action was outside the FTSE 100.

Trinity Mirror (LSE: TNI.L)
Newspaper publisher Trinity Mirror was one of the week's biggest risers, gaining 12 pence (20%) to 70 pence. The company, which replaced unpopular chief executive Sly Bailey earlier in the year, published upbeat guidance, telling us that operating profit should be in line with last year, at 104.5 million pounds.

The price has now nearly trebled since June's low point of 25 pence, though the stock is still lowly valued on a price-to-earnings ratio of less than 3. (LSE: MONY.L)
Financial comparison website has been a roaring success this year, climbing another 9 pence (6.3%) to hit a 52-week high of 155 pence on Friday, before settling back a little to 152 pence. The price is now up 65% on its 52-week low of 94 pence set back in late December.

Earnings forecasts for this year and next look strong, with growth of 20% and more expected, and dividends are building up to around the 4% level.

Balfour Beatty (LSE: BBY.L)
Construction firm Balfour Beatty is suffering, having slumped by 66 pence (16%) to 249 pence after warning of toughening market conditions. The U.S. construction market is depressed, while U.K. performance was described as "weaker than expected."

The company's work balance has shifted to smaller contracts, with major projects becoming thin on the ground. As a result, full-year profit expectations have been downrated by around 10 million pounds.

Royal Bank of Scotland (LSE: RBS.L)
The U.K.'s big banks fell back this week, with several of them having had to set aside yet more cash to cover their costs of mis-selling payment protection insurance (PPI). Royal Bank of Scotland was one of the biggest fallers, dropping 11 pence (4%) to 270 pence.

RBS had previously bumped its PPI compensation cash by an extra 400 million pounds, taking the total to 1.7 billion pounds, which makes a serious dent in its accounts.

What now?
As usual, this week's FTSE trading provided some large share-price movements -- and perhaps some buying opportunities. Indeed, legendary investor Warren Buffett has spent more than $1 billion buying the shares of one of the U.K.'s most successful FTSE large caps.

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.