I am having trouble updating an Excel Sheet using pandas by writing new values in it. I already have an existing frame df1 that reads the values from MySheet1.xlsx. so this needs to either be a new dataframe or somehow to copy and overwrite the existing one.

The spreadsheet is in this format:

[![enter image description here](https://i.stack.imgur.com/cmljr.jpg)](https://i.stack.imgur.com/cmljr.jpg)

I have a python list: values\_list = [12.34, 17.56, 12.45]. My goal is to insert the list values under Col\_C header vertically. It is currently overwriting the entire dataframe horizontally, without preserving the current values.

```
df2 = pd.DataFrame({'Col_C': values_list})
writer = pd.ExcelWriter('excelfile.xlsx', engine='xlsxwriter')
df2.to_excel(writer, sheet_name='MySheet1')
workbook  = writer.book
worksheet = writer.sheets['MySheet1']

```

How to get this end result? Thank you!

[![enter image description here](https://i.stack.imgur.com/NNqSb.jpg)](https://i.stack.imgur.com/NNqSb.jpg)