Currently the developed zoho project program calculates a percentage calculation on the project overview page. (See % area in picture below outlined in RED)

This is helpful but I believe another calculation would be more helpful as a substitution or in addition to the current calculation.

My suggestion would to calculate the numerator as SUM OF ALL (% COMPLETED OF TASK x TASK WORK PLANNED HOURS) and the denominator as (TOTAL TASK WORK PLANNED HOURS).

Changing this formula would give you a more accurate picture of your true completion percentage of a project.

Current setup shows a completion percentage of 50%. (1 of 2 tasks are done)

My suggestion would show as [(25*1)+(75*0)]/100 or 25% (25 estimated out of 100 estimated hours are completed)

Scenario 2: A project has two tasks. Task 1 has project completion of 50% and 50 work planned hours. Task 2 has a project completion of 0% and 50 work planned hours.

Current setup shows a completion percentage of 0%. (0 of 2 tasks are done)

My suggestion would show as [(50*.5)+(50*0)]/100 or 25 percent (25 estimated out of 100 estimated hours are completed)

After using that percentage it would be nice to see a table in task overview in zoho analytics tasks dashboard that would show the following statistics:

The % project complete would be filtered by the method mentioned above.

From there you could compare the %BUDGETED HOURS USED used to  % PROJECT COMPLETE to see if the project is trending ahead or behind schedule.