Scatterplot of the Birthrate Data

In this activity, you will be graphing a scatterplot of birth rate data collected from the United States Census Bureau for the years 1917 to 1974. The data consists of the number of births (in 100,000's) and the corresponding year. One would expect that, with the national population growing rapidly, the data would show a steady increase in the number of births. A scatterplot will reveal the pattern of birth rate throughout the years. Using either Excel or the TI-83 graphing calculator, create a scatterplot of the data to find a relationship between the national birth rate and the year.

This data exists in three files; one is in Excel Data format, one is in Text format, and one is in TI-83 Group format. If you want to create the scatterplot using the TI-83, you will have to import the text data into the calculator from the computer after you have downloaded the file.

What range of years contains the highest birthrates? Do you see a trend or pattern in the data? Describe it. What do you think could explain this trend? Estimate the birthrate for 1910 and for 1980. Is a scatterplot a good tool for extrapolating (making an assumption of the pattern of the data outside the range of the data)? What is the main reason for using a scatterplot?

Original work on this document was done by Central Virginia Governor's School students Christian Neeley (Class of '98) and Patrick Burke (Class of '99).

Copyright © 1998 Central Virginia Governor's School for Science and Technology Lynchburg, VA