Just so everyone knows, there are only two gramatically correct ways to write Seventies with numerals.
'70s (apostrophe, seven, zero, ess -- specifically an abbreviation for "1970s" -- notice that there is no apostrophe between the zero and the ess)
70s (seven, zero, ess -- specifically the numerical abreviation for "Seventies" -- again, no apostrophe between the zero and the ess)
—Captain the Reverend Lord C.S. Rowan, Lord of Glencoe, Minister of Pastafarianism, Gentleman Pirate
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