The quality of economic releases varies from nation to nation but the numbers can have a pronounced impact on markets. The standard of information from the UK's ONS is not bad by European standards, although it has faced criticism over recent years following its partial relocation to South Wales. As might be expected, standards in emerging markets are lower and this is something of an issue for investors as China takes on a pivotal role in the global economy.

Fortunately, the world's largest economy, the US, has a reputation for high quality economic statistics, produced both by the government and non-government organisations. Indeed, such is the dizzying wealth of reports, it is not always easy to identify the most important ones, particularly with many of today's media organisations increasingly focused on capturing eyeballs rather than imparting useful knowledge.

Paradoxically, the big daddy report, the GDP release, has often little market impact. This is a backward looking summary and a large number of its constituent parts are already known in advance of the formal release. Others such as the initial jobless claims are of trivial importance and, by themselves, inconsequential. However, as this release is a weekly one, news organisations often widely report on it.

This makes it easy to be confused with one of the most widely anticipated numbers, the BLS Employment Situation report. This is more often commonly referred to as 'non-farm payrolls' or even just the US 'jobs report'. This provides a useful monthly litmus test for the strength of the economy and can highlight any emerging bottlenecks in the labour market. Despite the report's importance, few seem to have much understanding of how this report is put together.

This month's jobs report caused some delightful mischief for pundits. The headline numbers reported that few new jobs were created in February (only 20,000) yet the unemployment rate tumbled from 4% to 3.8%. This might be explained by a shrinking labour force but the report detailed that this had actually held steady (at around 163m).

The solution to this head scratcher is only apparent once you learn that the two headline figures quoted in the jobs report are generated from completely different surveys. The unemployment rate is derived from a household survey. As the number of US households is huge, only a limited sample can be assessed which creates monthly volatility in the numbers. As a result the number is usually presented as a percentage. In contrast, the jobs number quoted in the report is derived from a survey of employers (the 'establishment data'). This provides much greater breadth than the household data, however, does suffer from various weaknesses such as the inclusion of data from new businesses.

Okay, it's kinda nerdy to know this sort of detail but it is of occasional use. I am no economist but actually an accountant by training and I know that understanding how numbers are presented is often extremely useful.