Question

The number of users of a certain website (in millions) from 2004 through 2011 follows:

Year Period Users (Millions)
2004 1 1
2005 2 5
2006 3 11
2007 4 58
2008 5 145
2009 6 359
2010 7 607
2011 8 846
Using Minitab or Excel, develop a quadratic trend equation that can be used to forecast users (in millions). (Round your numerical values to one decimal place.)

Answer 1

y = 26.3x² - 116.9x + 109.6

Explanation:

Given the data ;

Year Period Users (Millions)

2004 1 1

2005 2 5

2006 3 11

2007 4 58

2008 5 145

2009 6 359

2010 7 607

2011 8 846

A quadratic regression model can be obtained using a quadratic regression calculator ; The quadratic regression modeled obtained is in the form :

y = Ax² + Bx + C

y = 26.3x² - 116.9x + 109.6