Step 1: Break the phrase into its parts.
'Birth rate' measures births against population; 'crude' signals a basic, unadjusted ratio rather than an age specific one.
Step 2: Give the working definition.
It counts every live birth in an area during one year and divides that by the mid year total population, then multiplies by 1,000 to get a rate per thousand people.
Final Answer:
Crude birth rate expresses annual live births as a rate per 1,000 of the total population.$\boxed{CBR = (\text{Births}/\text{Population}) \times 1000}$