20,000 viewers out of 2.6 million is a pretty insignificant number. I would imagine 20,000 is within the margin of error when the calculate the viewers since it represents less than 1% of the total viewers.Actually, this is not a good number. The number of viewers keeps decreasing.
April 20th: 2.729 M
April 27th (going against nfl draft): 2.680 M
So, the only reason the viewership was so low last week was because of the NFL Draft. If you compare this number to the one on April 20th, it's actually a -20,000 viewers loss.