Excel Macro for Real-Time Data Logging

I'm looking for an experienced Excel developer to create a macro-enabled Excel file that automatically saves specific data points every minute. The data to be captured includes Mark To Market and Total Premium Sold from two different XTS IDs API. The saved data should be in Excel format, with new data appended to the existing data.

Key Requirements:
- Develop an Excel macro to log data every minute.
- Capture data from two XTS IDs API, specifically Mark To Market and Total Premium Sold.
- Save the data in Excel format, appending new data to the existing file.
- Implement API connection using an API key for authentication.
- Ensure the solution handles real-time data efficiently and accurately.

Ideal Skills and Experience:
- Strong proficiency in Excel macros and VBA.
- Experience with API integration and data handling in Excel.
- Ability to manage real-time data updates and ensure data integrity.
- Attention to detail and commitment to timely delivery.

If you have the expertise to develop this solution, I look forward to your proposal.