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Applications continue
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 3 |
After all data are entered (after last TL) press TL (COMPUTE) to obtain the so-called “y-intercept” value at point 0—the point at which the trend line, traveling the horizontal axis (time line), intersects the vertical axis (representing given units of quantity).
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| 4 |
Enter number of time period (any time value), press n.
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| 5 |
Press TL to obtain trend line value.
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| 6 |
Repeat step 5 to obtain each successive trend value per time unit, or go back to step 4 to find the values for a unique time position.
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Note 1: Time position can be seen at any time by pressing x y key—be sure to press x y again before resuming.
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Note 2: The slope (change in units of quantity per time period) of the trend line may be found by pressing R R .
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Sample Case: Sales figures for a six month period are:
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Month
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Sales ($ in thousands)
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1
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476
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2
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589
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3
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570
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4
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625
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6
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619
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5
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570
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Generate
a linear trend forecast of the second six months’ sales level based on
the first six months’ sales. How many entries are there? Find the
theoretical forecast values for the second six months.
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Solution
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| | Enter: | | | See Displayed: | | |
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CLx
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476 TL 589 TL 570 TL 625 TL 619 TL
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number of entries
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value of sales trend line at month 0
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extrapolated sales at month 7
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extrapolated sales at month 8
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