Today's labour market figures didn't just tell us about aggregate employment and wages. They also contain some less-noticed but also important data.

First, there are labour market flows - the numbers moving between employment, unemployment and inactivity. These show that:

- 338,000 people moved from employment to unemployment in Q4. This implies that 1.1% of those in work lost their jobs and didn't get another; this of course understates job insecurity to the extent that many who lose a job find another in the same calendar quarter, and because...

- 524,000 moved from employment to inactivity. In other words, most of those who lost their jobs in Q4 did not become unemployed. Many of these transitions would have been voluntary, such as folks retiring. But it's also the case that these moves include those who lost their jobs through illness or who just dropped out of the labour market.

- 491,000 people moved from inactivity to employment - equivalent to 21.6% of the inactive who wanted work in Q3. This compares to 522,000 moving from unemployment to work (26.6% of Q3's unemployed). This tells me that the inactive are a big source of labour. This implies that potential labour supply is much greater than official unemployment figures suggest: there are 2.28m "inactive" people who want a job compared to 1.86m officially unemployed. This, allied to falling productivity, makes me doubt whether real wages can rise by much.

We also got data on employees by socio-economic category (table EMP11 here). These show that, in the last 12 months, employment has shifted downmarket. The numbers in "routine occupations" rose by 7% whilst the numbers in the higher managerial and professional class fell by 0.2%. Since employment troughed in Q12010 routine occupations have risen 14.7% whilst the higher managerial and professional category has risen 8.7%.

We also have data on full-time wages by occupation. These show that wages of professionals have fallen in nominal terms in the last 12 months, by 2.1%. Wages of skilled trades, though, have risen 5.1%; given that employment of them has risen 6.1% this could be evidence that skill shortages are raising some wages. Wages of sales staff have gone up by 6.2%, although the numbers of them have fallen slightly. Since the Q1 2010 trough in employment, though, managers' pay has outstripped others, rising by 14.6% compared to an average of 6.6%.

We also have numbers on employment and self-employment by occupation. These show that since Q1 2010, employment of professionals has risen 10.4% and that of elementary occupations has risen 8.8%. Administrative and secretarial employment, however, has fallen. This is evidence of job polarization.