What is the formula for weighted average days late?

Deciphering Weighted Average Days Late: A Key Metric for Payment Performance

Understanding customer payment behavior is crucial for maintaining healthy cash flow. While simple averages can provide a glimpse into payment trends, they often fail to capture the full picture. Weighted Average Days Late (WADL) offers a more nuanced perspective by considering both the magnitude of outstanding payments and the duration of their tardiness.

Simply put, WADL gives more weight to larger overdue amounts that are significantly past their due date. A small invoice a few days late has less impact than a large invoice that’s weeks overdue. This makes WADL a more accurate reflection of the actual impact of late payments on your business.

Here’s a breakdown of the formula and how it works:

Formula:

WADL = (Σ (Overdue Amount * Days Late)) / Total Original Amount Due

Let’s break it down:

• Overdue Amount: This is the remaining balance on each individual invoice that is past its due date.
• Days Late: The number of days each invoice is past its due date. This is calculated from the due date to the current date (or the date of the report generation).
• *Σ (Overdue Amount Days Late):* This symbol (Sigma) signifies summation. You multiply the overdue amount by the days late for each* overdue invoice, and then add all these products together.
• Total Original Amount Due: This is the sum of the original amounts of all invoices considered in the calculation, regardless of whether they are currently overdue or not. This provides the context for the overall payment performance related to the total invoiced amount.

Example:

Let’s say you have three invoices:

• Invoice 1: Original amount: $100, 10 days late, Overdue amount: $100
• Invoice 2: Original amount: $500, 5 days late, Overdue amount: $500
• Invoice 3: Original amount: $200, Paid on time.

Calculation:

1. *(Overdue Amount Days Late) for each invoice:**

   • Invoice 1: $100 * 10 = $1000
   • Invoice 2: $500 * 5 = $2500

2. *Σ (Overdue Amount Days Late):** $1000 + $2500 = $3500

3. Total Original Amount Due: $100 + $500 + $200 = $800

4. WADL: $3500 / $800 = 4.375 days

Therefore, the Weighted Average Days Late is 4.375 days.

Why is WADL important?

• Improved Cash Flow Management: By pinpointing the most impactful late payments, businesses can prioritize collection efforts and improve cash flow forecasting.
• Performance Evaluation: WADL provides a more accurate measure of customer payment performance than a simple average.
• Credit Risk Assessment: Tracking WADL over time can help identify potentially problematic customers and inform credit risk assessments.
• Process Improvement: Consistently high WADL can indicate underlying issues with invoicing, payment terms, or collection procedures, highlighting areas for improvement.

By incorporating WADL into your analysis, you gain a more comprehensive understanding of customer payment behavior and its impact on your bottom line. This empowers you to make more informed decisions regarding credit policies, collection strategies, and overall financial planning.