2.3

• population pyramid/age-sex composition graph - shows the age and sex structure of a population; can also provide info on birth rates, death rates, life expectanc, and economic development
• cohorts - the vertical axis which show age groups
• birth deficit - a slow down of births
• baby boom - a spike in the birth rate
• baby bust - when the birth rates are lower for a few years
• echo - the previous baby boom which shows up as a bulge on the population pyramid
• potential workforce - any between the ages of 15-64
• dependent population - people under 15 and over 64
• dependency ratio - the comparison between the size of the potential workforce and the dependent population