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 1075.735 1031.1944 1120.276 1007.6159 1143.854
Jun 2025 1096.830 1052.2762 1141.384 1028.6907 1164.970
Jul 2025 1043.626 998.4236 1088.828 974.4951 1112.756
Aug 2025 1143.605 1085.6773 1201.532 1055.0124 1232.197
Sep 2025 1153.943 1095.9348 1211.951 1065.2273 1242.658
Oct 2025 1128.425 1069.1072 1187.742 1037.7064 1219.143
Nov 2025 1210.051 1143.5849 1276.517 1108.3999 1311.702
Dec 2025 1216.007 1149.3296 1282.685 1114.0326 1317.982
Jan 2026 1209.539 1141.1450 1277.932 1104.9396 1314.138
Feb 2026 1276.107 1203.1437 1349.070 1164.5193 1387.694
Mar 2026 1281.419 1208.0728 1354.766 1169.2456 1393.593
Apr 2026 1287.700 1212.4601 1362.941 1172.6303 1402.771
  • In March of 2026, the Costco stock price is forecasted to be 1281 dollars.

  • The width of the 80% prediction interval for this forecast in March of 2026 is 147 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 97.1% accurate.

  • This doesn’t guarantee that forecasts will be 97.1% 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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