The age distribution, , in Holderbank is; 43 children or 7.3% of the population are between 0 and 6 years old and 100 teenagers or 17.0% are between 7 and 19. Of the adult population, 23 people or 3.9% of the population are between 20 and 24 years old. 175 people or 29.7% are between 25 and 44, and 150 people or 25.5% are between 45 and 64. The senior population distribution is 71 people or 12.1% of the population are between 65 and 79 years old and there are 27 people or 4.6% who are over 80.