Scotland would need to cut public spending, increase taxes, or both if it was to survive independence.
A new study from the Institute of Fiscal Studies (IFS) said that failing North Sea oil revenues and an ageing population would create tough economic choices for the independent nation.
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Labour Education spokesperson Iain Gray said SNP ministers should be ashamed, as Scotland falls down international education rankings.
One of Scotland's foremost education academics has described today's figures on Scotland's standing in the world as "shocking".
Swinney says OECD statistics make for "uncomfortable reading" and pledges to press ahead with reform.