Last Update:

Monday, April 21, 2025

Opening Value:

993

Highest Value:

996.99

Lowest Value:

942.97

Adj. Closing Value:

957.77

  • 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
May 2025 1020.020 992.1966 1047.844 977.4676 1062.573
Jun 2025 1057.632 1021.8564 1093.407 1002.9181 1112.346
Jul 2025 1040.639 1001.0423 1080.236 980.0811 1101.197
Aug 2025 1078.996 1030.7567 1127.236 1005.2201 1152.773
Sep 2025 1101.194 1046.4517 1155.937 1017.4727 1184.916
Oct 2025 1109.142 1048.6020 1169.682 1016.5540 1201.730
Nov 2025 1135.794 1068.0224 1203.566 1032.1461 1239.443
Dec 2025 1154.963 1080.5524 1229.374 1041.1617 1268.765
Jan 2026 1170.867 1089.8329 1251.902 1046.9358 1294.799
Feb 2026 1192.877 1104.7255 1281.028 1058.0610 1327.692
Mar 2026 1211.776 1116.6237 1306.929 1066.2530 1357.299
Apr 2026 1230.122 1127.8508 1332.393 1073.7118 1386.532
  • In March of 2026, the Costco stock price is forecasted to be 1212 dollars.

  • The width of the 80% prediction interval for this forecast in March of 2026 is 190 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 95.5% accurate.

  • This doesn’t guarantee that forecasts will be 95.5% 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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