The total number of motorized 2-wheeler, 3-wheeler and 4-wheeler vehicles in BD is only about 3,420,000. Divide it by 365 days of a year. It comes only to 9,500 vehicles per day if all these vehicles of different types keep on moving over the Padma Bridge. But, you are talking about 21,300 vehicles per day. Your arithmetic does not match the reality.Around 21,300 veh/day (source: Prefeasibility study by JICA in 2005)
The number of years to reach break-even point: 20 years (source: Prefeasibility study by JICA in 2005) But trust me, the Padma bridge will reach the break-even point way earlier. 25 years was expected for the Bangabandhu bridge. However, it reached the break-even point within 12 years (Source: additional chief engineer, RHD).
The break even point may not come even after 500 years if the economic activities are not faster.
Sooooo?