## Lead Time
Lead Time is the time taken from placing an order till the material reaches the stores (godown).
It has four standard variants used across inventory-level formulas:
| Type | Meaning | Example |
|---|---|---|
| Emergency Lead Time | Time taken in an urgent procurement | e.g., 1 day |
| Minimum Lead Time | Shortest normal lead time | e.g., 3 days |
| Average Lead Time | (Min + Max) ÷ 2 | e.g., (3+7)/2 = 5 days |
| Maximum Lead Time | Longest normal lead time | e.g., 7 days |
### Why this matters
Lead time directly drives:
- Re-order Level (uses max consumption × max lead time)
- Minimum Stock (uses avg lead × avg consumption)
- Maximum Stock (uses min lead × min consumption)
- Danger Level (uses emergency lead × avg consumption)