Last Update:
Friday, March 27, 2026
Opening Value:
982.02
Highest Value:
987.11
Lowest Value:
978.11
Adj. Closing Value:
983.86
- The forecast plot shows the forecasted Costco stock prices for the next 12 months.
- The plot also shows the 80% prediction interval in dark purple and the 95% prediction interval in light purple.
- The numeric values for these forecasted values and prediction intervals are shown in the next tab.
The table below shows the forecast values and 80% and 95% prediction intervals for the 12 requested forecasts for the Costco stock.
| Point Forecast | Lo 80 | Hi 80 | Lo 95 | Hi 95 | |
|---|---|---|---|---|---|
| Apr 2026 | 956.8596 | 926.2656 | 987.4537 | 910.0700 | 1003.649 |
| May 2026 | 989.8227 | 949.7349 | 1029.9104 | 928.5137 | 1051.132 |
| Jun 2026 | 1024.6656 | 979.9505 | 1069.3807 | 956.2797 | 1093.052 |
| Jul 2026 | 1014.0495 | 959.2156 | 1068.8834 | 930.1883 | 1097.911 |
| Aug 2026 | 1023.0334 | 958.3119 | 1087.7549 | 924.0504 | 1122.016 |
| Sep 2026 | 1045.6992 | 973.9656 | 1117.4328 | 935.9921 | 1155.406 |
| Oct 2026 | 1050.2358 | 970.5277 | 1129.9438 | 928.3328 | 1172.139 |
| Nov 2026 | 1055.5864 | 967.3829 | 1143.7900 | 920.6908 | 1190.482 |
| Dec 2026 | 1069.7790 | 974.1799 | 1165.3781 | 923.5728 | 1215.985 |
| Jan 2027 | 1078.8289 | 975.9494 | 1181.7084 | 921.4883 | 1236.169 |
| Feb 2027 | 1085.3432 | 974.9467 | 1195.7396 | 916.5064 | 1254.180 |
| Mar 2027 | 1095.6430 | 978.0984 | 1213.1877 | 915.8740 | 1275.412 |
- In March of 2027, the Costco stock price is forecasted to be 1085 dollars.
- The width of the 80% prediction interval for this forecast in March of 2027 is 221 dollars.
These three residual plots allow the analyst to examine the distribution of the residuals of the modeled time series.
Despite increasing volatility, our stock price model is estimated to be 95.6% accurate.
This doesn’t guarantee that forecasts will be 95.6% accurate but it does improve our chances of accurate forecasting.
This dashboard was created using Quarto in RStudio, and the R Language and Environment.
The dataset used to create this dashboard was downloaded from Yahoo Finance.
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