Here is Chart 4 in our occasional quiz! Today’s chart focuses on the changing nature of the UK labour market in recent years. There are two data series to identify - in each case the chart shows the monthly level of each variable - look carefully at the two axes, a split scale is being used. Data A refers to the right hand axis and Data B refers to the left hand axis.

Can you identify what is being shown here? The answer to chart quiz 3 can be found below.

Here is the answer to the last Chart Quiz (3)

The chart shows the annual balance of trade in oil. For many years the UK has been a net exporter of oil because of revenues from exports of oil in the North Sea. But exploration and production of North Sea oil has declined greatly over the years and the UK has now returned to being a net importer of crude oil - indeed the deficit widened considerably in 2011 partly because of the surge in world oil prices back above the $100 a barrel level.