The Spanish government has admitted to making a typographical error which increased the country's public debt figure by about $14.5 billion.

Four days after announcing the national 2014 debt figure to the world, the economy ministry has issued a correction.

"It is an erratum," an economy ministry spokeswoman said.

It turns out that Spain's public debt in 2014 is expected to be the equivalent of 98.9 per cent of total economic output, not the originally published figure of 99.8 per cent, or 1.05 trillion euros ($1.53 trillion).

The error was not due to a problem in mathematical computations. Rather, the person who typed the number just mixed up the last two digits.

The difference may seem minimal, but when dealing with an economy the size of Spain's, which is the fourth biggest in the eurozone, it is equivalent to about 10 billion euros (about $14.5 billion).

Even after trimming the excess 10 billion euros from the forecast, economists say Spain's debt is rising at a worrying speed as it struggles to emerge from a double-dip recession triggered when a property bubble imploded in 2008.

Spain's public debt soared from 68.5 per cent of total economic output in 2011 to 85.9 per cent at the end of 2012 and 92.2 per cent mid-way through this year.

Prime minister Mariano Rajoy, whose right-leaning government has imposed an austerity regime to fix the state's accounts, expects the public debt this year to rise to the equivalent of 94.2 per cent of total economic output.

AFP