HP 12C manual 22.00 23.00 23.25 25.25 23.69 27.13 25.95

1.Key in the number 1 and press .

2.Key in the selected and press 0 1.

3.From the selection routing or from a previous forecast:

oKey in the smoothed average St-1and press 2.

o Key in the trend Tt-1and press 3.

oKey in the forecast t+1 and press 6.

4.Key in the current data value and press . The output is the error in forecasting the value just entered.

5.Press . The displayed value represents the forecast for the next period.

6.Record the following values: 0 (α), 2 (St-1), 3 (Tt-1)

and 6 (Dt+1) for use as initial values in the next forecast. You may

also wish to record 5 (Dt).

7.Repeat steps 4, 5, and 6 for the next forecast if available.

Example: Select the best smoothing constant based on sales (in thousands of dollars) of 22, 23, 23, 25, 23, 27, 25. Given the current sales in month 8 of 26, forecast the following month. Select the smoothing constant (α):

	Keystrokes	Display
	CLEAR	0.00
1		1.00
.5	0	0.50
	1	0.50
22	2	22.00
23	6	0.00
		23.00
23		23.25
25		25.25
23		23.69
27		27.13
25		25.95

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