Table 1. Number of facial images in each five-year age group within the FG-NET dataset. The dataset is partitioned into 14 age groups to mitigate data imbalance and facilitate age-specific model training. The table shows a significant decrease in sample count as age increases, particularly for groups over 40 years.

Age group	Age intervals	No. of samples
1	0–4	193
2	5–9	178
3	10–14	174
4	15–19	165
5	20–24	84
6	25–29	60
7	30–34	46
8	35–39	33
9	40–44	28
10	45–49	18
11	50–54	12
12	55–59	3
13	60–64	6
14	65–69	2