LONDON -- The FTSE 100 has been having another of those erratic weeks, sliding over the first few days. But it was lifted toward the end of the week by news that the U.K.'s trade gap is narrowing as exports improve, and by upbeat economic news from China. Overall, the index of top U.K. stocks ended the week down 65 points (1%) at 6,583, still 293 short of May's 13-year record of 6,876. But which stocks had the greatest effect during the week? Here are four of the biggest ups and downs.

Aviva (AV -0.47%)
Aviva told us of a 17% uplift in new business in first-half results released Friday, and that helped raise the stock price by 26 pence (6.8%) to 402 pence. The life insurer also revealed an interim pre-tax profit of 776 million pounds, against a loss of 624 million in the same period last year. Forecasts put Aviva on a forward price-to-earnings multiple of under 10, with a dividend yield of 4.2% expected. Look tasty? It does to me.

Anglo American (AAL 1.92%)
The latest news from China gave London's mining sector a boost, with Anglo American enjoying the biggest benefit with a price rise of 86 pence (5.9%) to 1,543 pence. Factory output in the People's Republic rose 9.7% in July over a year previously, compared with 8.9% in June, and inflation was steady at 2.7%. Although experiencing the biggest mining gain this week, Anglo American has suffered more pain than its peers with its price still down 25% over the past year.

HSBA Holdings (HSBA -0.10%)
It was time for half-year figures from HSBA Holdings on Monday, and they disappointed the markets, with the result that the bank's shares shed 44.9 pence (5.9%) to end the week at 710 pence. The fall was perhaps surprising, as the results weren't bad at all -- although revenue was down 7%, first-half earnings per share gained 20% and the interim dividend was lifted 11% to 10 cents per share.

easyJet (EZJ -0.51%)
What usually happens each month is that budget airline easyJet releases better-than-expected passenger statistics and the stock price rises further. But July was an anomaly -- although there was a 2% rise in passenger numbers announced on Tuesday, the load factor fell from 92.5% to 91.6%. And the shares fell, by 71 pence (4.9%) to close Friday at 1,377 pence. Still, easyJet is up nearly 150% over the past 12 months.

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