Tesco has been the doyen of the supermarket sector in the UK for the last decade. Other groups have struggled - Sainsbury, for instance, lost market share, while Morrisons had a couple of terrible years after the over-ambitious acquisition of Safeway - but Tesco seems invincible.
Or at least, it did seem invincible. But this year, for the first time, it's seen sales growth falling below the other supermarkets - and has started losing market share. At the same time, other supermarkets seem to have become stronger - Sainsbury has begun to turn itself around, Asda has been a strong competitor under Wal-Mart's ownership, and Waitrose - which you might have thought would be a recession victim with its upper middle class customer base and quality, rather than price, promise - has seen some truly stunning performance after it introduced its own budget range.
Waitrose has also made a land grab for the online market, having gained 20 percent share of online supermarket sales - far ahead of its 4 percent of the total supermarket revenues - with its Ocado operation. Still, online sales only make up 2 percent of the total grocery market at the moment, so that's not likely to worry Tesco management unduly.
September saw Tesco fighting back, with strong sales - up 4.5 percent on a like-for-like basis  . According to Nielsen, this boosted Tesco's market share to 28.5% according to Nielsen. Even so, other rivals are growing faster - Asda at 6.6%, Sainsbury at 5.7%, Morrison at 8.4% and Waitrose, almost incredibly, at 11.6% 
The interim results disappointed investors, with the weakest first half profit growth in 11 years  - a mere 1.5 percent increase in declared pretax profits. (That figure is, true, a little ungenerous, as there were one-off expenses that need to be taken into account - the writedown of goodwill on operations in Japan, together with costs of the Tesco Bank acquisition. Take those costs out, and you'd see a 9 percent increase in profits - not dusty at all.)
Analysing the first half into its quarters also shows that growth had slowed from 4.3 percent to 3.1 percent in Q2, predominantly the result of weakening food price inflation. That doesn't give a lot of confidence for the rest of the year. But management hasn't lost faith,…