Excel VBA Manual Calculation on Workbook Open

This article provides a comprehensive guide on implementing VBA manual calculation on workbook open, taking into account diverse user requirements and scenarios.

In the fast-paced world of professional data analysis, accuracy, and efficiency are paramount. When working with large and complex Excel workbooks, the automatic calculation can sometimes lead to delays and inaccuracies. That’s where VBA manual calculation on workbook open comes into play.

By leveraging this powerful feature, professionals have greater control over their data by optimizing performance. Practically, it enhances our Excel workflows and helps us to excel in data analysis.

User Benefits of VBA Manual Calculation in Excel

The use of VBA manual calculation in Excel offers several key benefits to users. First, it improves performance when working with large datasets or complex calculations, allowing for faster processing and smoother workflow.

Secondly, it offers selective and controlled calculation options, enabling users to choose when and which calculations they want to perform, saving time and resources. Additionally, It provides greater control over workbook management, as users can customize the calculation options to suit their specific needs.

In short, it enhances the speed and efficiency of workbook processing, resulting in improved performance and a more responsive Excel environment.

Excel VBA Manual Calculation on Workbook Open: 2 Use Cases

If you’re looking to take control of the calculation process in Excel, utilizing VBA code provides a powerful solution to meet your requirements. By utilizing this approach, you can switch the calculation mode from automatic to manual, allowing you to trigger manual calculation upon the workbook opening using VBA.

There are three common scenarios where utilizing VBA manual calculation on a workbook open proves beneficial.

Consider that in a retail store dataset, we have information on 5 products. The dataset includes the quantity purchased and the cost price for each product. We will determine the cost price/quantity by dividing the cost price by the quantity. The store aims to make a $5 profit on each quantity and sets the sale value by adding $5 to the cost price. We will calculate the benefit column then to determine the revenue generated from each quantity.

1. Single Active Workbook

To activate manual calculation on workbook open, you can follow these steps. Firstly, go to the developer tab in Excel. From there, select Visual Basic or use the keyboard shortcut Alt+F11 to open the Visual Basic window.

Once the window is open, go to the menu and choose Insert, then click on Module. This will open the module where you can insert the necessary code.

Now we will use the following code to stop automatic calculation on workbook open.

Sub Open_WKB()
Application.Calculation = xlCalculationManual
Application.CalculateBeforeSave = True
End Sub

To execute the code choose Run from the standard menu or use the keyboard shortcut F5.

Once the code is executed, changes made to the data won’t trigger any calculations. For instance, modifying values in the quantity column will not affect other columns dependent on the quantity column.

Upon closing the window, exiting the workbook, or saving the file, the values automatically update. When reopening the dataset, you will see the updated values.

When you reopen the dataset, the calculation mode will remain manual mode, ensuring that any changes made to the dataset won’t trigger calculations. However, it is important to note that upon closing the dataset, the values will update by performing all the necessary calculations.

2. Specific Sheet of an Active Workbook

When you modify the calculation process for a specific workbook, it has an impact on all the sheets within that workbook. However, there may be instances where you need to activate manual calculation for a specific sheet, particularly when dealing with large and complex data that takes significant time to process. In such cases, you can follow the example outlined below.

Let’s consider an example where we have a dataset for revenue calculation for three months March, April, and May. Our goal is to enable manual calculation for the sheet corresponding to the month of May, while the calculation process for the other sheets remains inactive.

This prevents unnecessary calculations and speeds up the performance of the workbook.

First, we need to open the Excel VBA module.

Then we will apply the following code.

Sub DisableManualCalculation()
'Produced by ExcelDemy
Dim ws As Worksheet
Dim rng As Range
Dim cell As Range
Dim flagCell As String
flagCell = "$B$12"
With Application
.Iteration = True 'Enable iterative calculation
.MaxIterations = 1 'Set maximum iterations to 1
End With
Dim Arr() As Variant
Index = 0
For Each ws In ThisWorkbook.Worksheets
' Loop through all cells with formulas
For Each cell In ws.UsedRange
If cell.HasFormula Then
' Update the formula to the new structure
Index = Index + 1
ReDim Preserve Arr(1 To Index)
Arr(Index) = cell.Formula
End If
Next cell
Next ws
Count = 0
' Loop through all worksheets
For Each ws In ThisWorkbook.Worksheets
' Loop through all cells with formulas
For Each cell In ws.UsedRange
If cell.HasFormula Then
' Update the formula to the new structure
Count = Count + 1
cell.Formula = "=IF(" & flagCell & "=""Calculate"", " & Mid(Arr(Count), 2) & ", " & cell.Address(False, False) & ")"
End If
Next cell
'Update the worksheet with disbaled calculation
If ws.Range(flagCell) <> "Calculate" Then
ws.Range(flagCell) = "Calculate"
ws.Range(flagCell) = ""
End If
Next ws
End Sub

Now press F5 to run the code.

In the image above, you may notice that the calculations for all the sheets are missing or showing zero. This happens when the flagcell value “Calculate” is missing in cell B12 of each sheet.

When a sheet has the flagcell value in cell B12, it means the calculation process is active for that sheet. You can make changes, delete or manipulate your data as needed. Once you save the file or press Ctrl+S, the data will be automatically updated.

However, if you switch to other sheets, like the one for April, you won’t see any changes in the dataset. This is because there is no flagcell value specified for that particular sheet.

VBA Manual Calculation for One Workbook in Case of Multiple Active Workbooks

To have manual calculation for a specific workbook while keeping others in the automatic calculation, you must manually switch the calculation mode whenever you switch between workbooks. Excel does not provide a built-in feature to automatically handle different calculation modes for different workbooks.

Therefore, in Excel, the calculation mode applies to all open workbooks, so you can’t have different calculation modes for different workbooks simultaneously.

In VBA, if you have Intellisense enabled, you’ll notice that the Workbook object doesn’t have a .Calculate method. This means you can’t calculate an entire workbook using VBA alone.

Instead, you have 2 options:

1. Calculate all open workbooks (Manually or Automatically) or
2. Calculate (Manually or Automatically) all the sheets within a specific workbook.

Excel doesn’t provide the capability to calculate a single entire workbook through VBA.

To change the calculation process for a specific workbook among multiple active workbooks in Excel, select the desired workbook, go to the Formula tab, and choose the calculation options from the calculation group.

Thus, you can manually switch the calculation mode each time you switch between workbooks.

Excel VBA Force Calculation

In Excel, there are several situations where you may need to force recalculation to ensure accurate results. Firstly, if Excel is set to manual calculation mode, formulas won’t update automatically, leading to outdated values.

Secondly, changes to underlying data may not trigger an automatic recalculation, causing inaccuracies. Thirdly, volatile functions, such as NOW or RAND, may not recalculate unless there is a change in the worksheet.

Lastly, formula dependencies can result in calculations not updating automatically.

Consider a situation where you have modified the data in the quantity column of a worksheet, but the corresponding calculations in other columns are not updating automatically.

To force recalculation in this scenario, you can utilize the following VBA code.

Sub RecalSheet()
EnableCalculation = False
EnableCalculation = True
Calculate
End Sub

After executing the provided code, you will notice that the changes made in the quantity column are reflected in the subsequent columns. The code forces a recalculation, ensuring that the updated values are accurately calculated and displayed.

If you want to force recalculation in the whole workbook you can apply the following code.

Sub Force_Cal()
Dim WKB As Worksheet
For Each WKB In Worksheets
WKB.Calculate
Next WKB
End Sub

Tips: Pressing the F9 key in Excel forces a recalculation, updating all formulas and displaying the updated values immediately.

How to Turn Off Manual Calculation in Excel

To turn off manual calculation in Excel, you have two options. The first option is to go to the Formula tab, select Calculation Options from the Calculation group, and choose either Automatic or uncheck Manual from the drop-down menu.

Alternatively, you can use VBA code to disable manual calculation.

Sub Turnoff_Manual()
Application.Calculation = xlCalculationAutomatic
Application.CalculateBeforeSave = True
End Sub

By running this code, you can effectively disable manual calculation and enable automatic calculation in Excel.

Things to Remember

• If multiple workbooks are active, a change in the calculation mode applies to all open workbooks.
• Workbook object doesn’t have a .Calculate method.
• In case of choosing a specific sheet of a workbook, Run the code only once.
• Enabling iteration calculation sometimes cause a problem for other calculation.

Frequently Asked Questions

• What is the purpose of enabling manual calculation on workbook open?

Enabling manual calculation on workbook open provides users with enhanced control over calculation timing. This feature is particularly valuable when working with large datasets or complex formulas, as it contributes to improved workbook performance.

• What happens if I forget to enable manual calculation on workbook open?

If you do not enable manual calculation on workbook open, Excel will default to automatic calculation mode. In this mode, calculations are performed automatically whenever there are changes in the data.

• Can I use manual calculation for specific worksheets or ranges only?

The manual calculation mode in Excel applies to the entire workbook and affects all worksheets and ranges within it.

You can manually calculate the entire workbook using VBA by using the Application.Calculate method. However, you cannot set manual calculation mode for specific worksheets or ranges directly through VBA.

• Is manual calculation recommended for all workbooks?

The manual calculation is not suitable for all workbooks. You can used in specific cases where you need more control over when calculations occur. Automatic calculation is generally sufficient for most workbooks, providing real-time updates as data changes.

• Are there any specific considerations when using manual calculation in VBA?

When using manual calculation in VBA, ensure proper handling of dependencies, pay attention to calculation order, and consider efficiency and error handling for accurate results.

• Can I switch back to automatic calculation mode after enabling manual calculation on workbook open?

Yes, you can switch back to automatic calculation mode at any time.

Download Practice Workbook

You can download the workbook, where we have provided a practice section on the right side of each worksheet. Try it yourself.

Conclusion

In conclusion, Excel VBA manual calculation on workbook open offers users the ability to control calculation timing, enhancing performance and efficiency for workbooks containing large datasets and complex formulas.

In certain cases, users may prefer to utilize manual calculations in Excel. One effective approach is to apply the manual calculation to a single active workbook. This allows users to have precise control over when they are in a meeting or business activities.

However, it is crucial to manage dependencies and consider the implications of workbook functionality. Overall, Excel VBA manual calculation provides a valuable solution for optimizing calculations in Excel workbooks.

If you like this article, check Exceldemy for more relevant content.