The following data represents a study of a main street in your town
USA. The city monitored speeds on main-street before a stop light was
installed. They then conducted a study after a stop light was
installed to see if there was an effect on the speed of the cars
cruising down main-street. At 95% level of confidence.  Was there and
why?


Direction		Before the Stop Light	After Stop Light

9 am Westbound	32.1				32.2
9 am eastbound		32.2				32.9

1 pm westbound		32.6				32.4
1 pm eastbound		33				31

8 pm westbound		31.2				31.4
8 pm eastbound		33.5				31.6

if you put this data into a spreadsheet and look at it in a very basic way

32.1 - 32.2 = -.1
32.2 - 32.9 = -.7
32.6 - 32.4 = .2
33   - 31   = 2
31.2 - 31.4 = -.2
33.5 - 31.6 = 1.9

Average Decrease = (-.1-.7+.2+2-.2+1.9)/6 = .51

So overall there was a decrease in speed...but it was very minimal.
Don't know if this is what you were looking for or not. Hope it helps

95% condidence level refers to normally disrtibuted sets of data.
Since you only have one figure for each, you cannot perform any
statistical analysis.