Unemployment is at a 10-year low, wages are rising at a robust rate, and the state budget ran a surplus last year, yet ČSSD approved a long-term agenda over the weekend that states that the low overall tax burden is undermining the state budget and forcing broad cuts in spending.
Source: http://www.fsfinalword.com/data/FW170313.pdf
Do you think that the passage in bold is standard? "Low" is after all the adjective so why is there the indefinite article?
Is it possible to rewrite this sentence this way: Unemployment is at the lowest level since 10 years?