Question 1203742
i used the two sample z-score proportion calculator at <a href = "https://www.socscistatistics.com/tests/ztest/default2.aspx" target = "_blank">https://www.socscistatistics.com/tests/ztest/default2.aspx</a> to solve this.
the results are shown below:


<img src = "http://theo.x10hosting.com/2023/091911.jpg">


calcuator says test alpha = .00086 which is significantly less than the critical alpha of .10.
this indicates the results are significant, meaning that the sample difference is more then likely real and not just a result of random differences in sample proportions.
the conclusion is that the proportions between 1990 and 2010 have changed, meaning that the different sample proportions are not due to random variations in sample proportions.


i checked the results manually and they agree with the calculator results that indicates the results are significant by a wide margin.


the method used is in the following reference.


<a href = "https://sixsigmastudyguide.com/two-sample-test-of-proportions/" target = "_blank">https://sixsigmastudyguide.com/two-sample-test-of-proportions/</a>


the pooled version was used.