I got the answer from Boychuk Mikhail. Hope it helps.
- Worst URLs (by average response time)
a) “Layers breakdown of the URL” - This bar shows total response time (in seconds) and the coloring of this bar shows how much time was spent by every layer. Under the table you can see the legend with layers (also you can see this layers on “Page Download Time Breakdown”).
b) “Count” column – is total number of hits on URL.
2. Most Resource Consuming URLs
a) The resource is Server Time (I think it means CPU time in seconds).
b) “Count” column – the same as above. “Total”, “Min” and “Max” are zero because they are too small.
3. Largest URLs by Average KBytes
a) Average Size column represents AVG column value (in KBytes) in the form of a bar to visualize the largest URL’s. Under this column in table you can see five cell ruler with marked border values.
b) “Count” column – as in previous two tables.
