A logistics company is applying Lean accounting to its warehouse operations. Calculate the Inventory Turnover Ratio for a warehouse that had $1,000,000 in sales and average inventory of $200,000. Propose measures to optimize inventory levels based on the Inventory Turnover Ratio calculation. Discuss the importance of optimizing inventory in Lean supply chain management.

Requirements:

1. Calculate the Inventory Turnover Ratio.
2. Propose measures to optimize inventory levels.
3. Discuss the importance of optimizing inventory in Lean supply chain management.