For which ending year did the decadal percentage growth in the number of cars,…

Concept

Decadal percentage growth compares a value with its value ten years earlier.

Growth (%) = ((later value - earlier value) / earlier value) × 100. Calculate this rate separately for the combined cars, jeeps and taxis category and for two-wheelers for each ending year, then compare the two rates.

Application

1. For 1981: Cars, jeeps and taxis = ((11.60 - 6.82) / 6.82) × 100 ≈ 70.09%; two-wheelers = ((26.18 - 5.76) / 5.76) × 100 ≈ 354.51%. The growth rate for cars, jeeps and taxis is lower.

2. For 1991: Cars, jeeps and taxis = ((29.54 - 11.60) / 11.60) × 100 ≈ 154.66%; two-wheelers = ((142.00 - 26.18) / 26.18) × 100 ≈ 442.40%. The growth rate for cars, jeeps and taxis is lower.

3. For 2001: Cars, jeeps and taxis = ((70.58 - 29.54) / 29.54) × 100 ≈ 138.93%; two-wheelers = ((385.56 - 142.00) / 142.00) × 100 ≈ 171.52%. The growth rate for cars, jeeps and taxis is lower.

4. For 2011: Cars, jeeps and taxis = ((191.23 - 70.58) / 70.58) × 100 ≈ 170.94%; two-wheelers = ((1018.65 - 385.56) / 385.56) × 100 ≈ 164.20%. Here the growth rate for cars, jeeps and taxis is higher.

Cross-check

Using growth factors gives the same comparison: for 2011, the cars, jeeps and taxis factor is 191.23 / 70.58 ≈ 2.71, which exceeds the two-wheeler factor 1018.65 / 385.56 ≈ 2.64.

Result

Therefore, the required ending year is 2011.