Question 1118675
You may want linear models.  


This is not a complete solution, but just a way to start analyzing the description.  You want some data points.


<pre>
Year  Set to time 0=1990    Price Per Person/Service Member   POINTS (t,p)
1995          5                80000                        (5, 80000)
2000          10               90000                        (10, 90000)
</pre>

<pre>
Year         time 0=1990         Number of Service Members    POINTS (t, n)
1990            0                 2000000                    (0,2000000)
2000           10                 1500000                   (10,1500000)
</pre>


You use each pair of points to get linear equations for each.  Next, COST would be price multiplied by number of members, or   {{{p*n}}}.  Be careful to notice, the two first sets of data points are based on a different time point value; so you may need to compute the needed price  to use for getting cost or Number of Members equation.


The actual question is about year 1998, for when t=8.