in order to draw a scatter diagram we need interval data for
Scatter plot A scatter plot can be used either when one continuous variable that is under the control of the experimenter and the other depends on it or when both continuous variables are independent. If a parameter exists that is systematically incremented and/or decremented by the other, it is called the control parameter or independent variable and is customarily plotted along the horizontal axis. The measured or dependent variable is customarily plotted along the vertical axis. If no dependent variable exists, either type of variable can be plotted on either axis and a scatter plot will illustrate only the degree of correlation (not causation) between two variables.
Population pyramid Population pyramids often contain continuous stacked-histogram bars, making it a horizontal bar diagram. The population size is depicted on the x-axis (horizontal) while the age-groups are represented on the y-axis (vertical).[3] The size of the population can either be measured as a percentage of the total population or by raw number. Males are conventionally shown on the left and females on the right. Population pyramids are often viewed as the most effective way to graphically depict the age and distribution of a population, partly because of the very clear image these pyramids represent.[4]A great deal of information about the population broken down by age and sex can be read from a population pyramid, and this can shed light on the extent of development and other aspects of the population.