A company uses a 5-year period to adjust its dividend payout ratio towards a target payout ratio of 40%.
Last year, the company earned $2.50 per share, and paid a dividend per share of $0.50.
This year, the company is expected to earn $3.0 per share.

According to the target payout ratio approach:

The expected dividend this year = Last dividend + (Expected increase in earnings × Target payout ratio × Adjustment factor), where Adjustment factor = 1/ period to adjust dividend
The expected dividend this year = $0.50 + [($3.0 - $2.5) × 0.40 × 1/5] = $0.54

My question is:
How can the company narrow the gap between its actual payout ratio and the target payout ratio using the target payout ratio approach?
Suppose that every year, the company's increase in earnings is 1, its increase in dividend is only Target payout ratio × Adjustment factor = 0.40 × 1/5 = 0.08. The gap is getting bigger and bigger.
It seems to me that, if the company can maintain its current level of earnings, it can never reach the target payout ratio.