natrx - those you have given up looking for work have always been excluded from unemployment numbers,  they are however captured in the % of labour market participation.

For the US currently 62.8% of those over 16 are participating in the labour market.
(numbers for October) the higher percentage participation in the last 10 years was 66.4% in December 2006.  With an unemployment rate of 4.4 %

Now that was at some high employment,  apparently the labour market participation rate peaked at 67.3 in April 2000, which was its highest point between 1980 -2016