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This section of freeway wastes 94 hours of peoples’ time per week, the study calculated.

Huh? What does that mean? There are only 168 hours in a week, so this implies that the average driver is stuck in traffic over 13 hours a day. That makes no sense at all.

Here is their methodology for determining congestion values in bottleneck areas such as the Cross Bronx Expressway that you mention:

http://scorecard.inrix.com/scorecard/methodology.asp

Bottlenecks

Each road segment’s bottleneck factor can be compared with others in a metropolitan area and against all bottlenecks nationally. It can also be compared year-to-year, as we have in this Scorecard.

Congestion – and how to measure it – can be in the eye of the beholder. Is congestion defined as how bad a road segment is at its worst or is it how often the segment gets “congested” (and what is the threshold for “congestion” anyways – tapping the brakes, stop and go conditions, etc.)? INRIX has developed a method that combines both the amount of time a road segment is congested with the intensity of congestion during those periods. The process used to analyze each of the road segments is as follows:

The same RS and HS values are utilized as in the overall congestion by metropolitan area portion of the study;
All 168 hours of the week are considered, not just the 40 “peak hours.” As will be evident in the data, severe bottlenecks aren’t just limited to peak hours;
For each hour of the week that the average speed is less than 50% of the reference speed, the hour is considered “congested;”
For all “congested” hours, the average intensity of the congestion is determined by establishing an average travel time ratio;
The total Bottleneck factor equals the number of hours of congested by the average travel time ratio.
Each road segment’s Bottleneck factor can be compared with others in a metropolitan area and against all Bottlenecks nationally. It can also be compared year-to-year, as we will do going forward.

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The way that the congestion figure was expressed in the article is not particularly well stated in my view. I think that it would be more accurate to say that the road is congested for so many hours over the course of an average week, as opposed to it 'wasting x hours of peoples' time'. The way they're expressing it in the article would be the case only if people spent 100% of their time every week on that particular road ;-)