Unemployment is not a lagging indicator. Those who say this don't know what they're talking about. Once an employee is layed off they start to spend less money. Spending less money going forward creates less demand.
your own data shows the lag. unemployment was 4.0-4.1 for the blowoff bull top and didn't exceed that level until feb '02. that's a year later. unemployment was lower in Dec '00 than in Mar '00.