**How to Use the LN Function in Microsoft Excel**

### Part 1: Introduce

๐ **Definition**

The LN function in Microsoft Excel returns the natural logarithm of a number. Natural logarithms are based on the constant e (approximately equal to 2.71828182845904).

๐ **Purpose**

The Purpose of the LN function is to compute the natural logarithm of a given positive real number.

๐ **Syntax & Arguments**

```
LN(number)
```

**Number**(Required): The positive actual number for which you want the natural logarithm.

๐ **Explain the Arguments in the function**

**Number**: This is the positive actual number whose natural logarithm you wish to determine.

๐ **Return value**

The LN function returns the natural logarithm of the specified number.

๐ **Remarks**

The LN function is the inverse of the EXP function in Excel.

### Part 2: Examples

**Example 1: Finding the Natural Logarithm of a Business Revenue**

**Purpose of illustration:**To determine the natural logarithm of a company’s monthly revenue.**Data sheet and formulas:**

A | B | C | |
---|---|---|---|

1 | Monthly Revenue ($) | Formula | Result |

2 | 50000 | `=LN(A2)` | 10.819778 |

**Explanation:**The natural logarithm of the monthly revenue ($50,000) is approximately 10.82.

**Example 2: Calculating the Natural Logarithm of Product Sales**

**Purpose of illustration:**To compute the natural logarithm of the number of products sold.**Data sheet and formulas:**

A | B | C | |
---|---|---|---|

1 | Products Sold | Formula | Result |

2 | 1500 | `=LN(A2)` | 7.313220 |

**Explanation:**The natural logarithm of the number of products sold (1,500) is approximately 7.31.

**Example 3: Natural Logarithm of Client Sign-ups**

**Purpose of example:**To determine the natural logarithm of client sign-ups in a month.**Data sheet and formulas:**

A | B | C | |
---|---|---|---|

1 | Client Sign-ups | Formula | Result |

2 | 300 | `=LN(A2)` | 5.703782 |

**Explanation:**The natural logarithm of the number of client sign-ups (300) is approximately 5.70.

**Example 4: Natural Logarithm of Website Visits**

**Purpose of example:**To compute the natural logarithm of the number of website visits.**Data sheet and formulas:**

A | B | C | |
---|---|---|---|

1 | Website Visits | Formula | Result |

2 | 10000 | `=LN(A2)` | 9.210340 |

**Explanation:**The natural logarithm of the number of website visits (10,000) is approximately 9.21.

**Example 5: Natural Logarithm of Social Media Followers**

**Purpose of illustration:**To determine the natural logarithm of the number of social media followers.**Data sheet and formulas:**

A | B | C | |
---|---|---|---|

1 | Followers | Formula | Result |

2 | 5000 | `=LN(A2)` | 8.517193 |

**Explanation:**The natural logarithm of social media followers (5,000) is approximately 8.52.

**Example 6: Using LN with IF for Website Visits**

**Purpose of example:**To compute the natural logarithm of website visits only if they exceed a certain threshold.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Threshold | Website Visits | Formula | Result |

2 | 5000 | 6000 | `=IF(B2>A2, LN(B2), "Below Threshold")` | 8.699514 |

**Explanation:**The formula checks if the website visits (6,000) exceed the threshold (5,000). Since it does, it returns the natural logarithm of the holidays, approximately 8.70.

**Example 7: Using LN with SUM for Monthly Sales**

**Purpose of example:**To compute the natural logarithm of the sum of monthly sales.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Jan Sales | Feb Sales | Formula | Result |

2 | 3000 | 4000 | `=LN(SUM(A2:B2))` | 8.517193 |

**Explanation:**The formula sums up the sales of January and February (total 7,000) and then computes its natural logarithm of approximately 8.52.

**Example 8: Using LN with VLOOKUP for Product Prices**

**Purpose of example:**To find the natural logarithm of the price of a specific product using VLOOKUP.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Product | Price | Formula | Result |

2 | Apple | 1.2 | `=LN(VLOOKUP("Apple", A2:B2, 2, FALSE))` | 0.182322 |

**Explanation:**The formula looks up the price of “Apple” and then computes its natural logarithm, approximately 0.18.

**Example 9: Using LN with AVERAGE for Weekly Hours Worked**

**Purpose of illustration:**To compute the natural logarithm of the average hours worked in a week.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Mon Hours | Tue Hours | Formula | Result |

2 | 8 | 9 | `=LN(AVERAGE(A2:B2))` | 2.197225 |

**Explanation:**The formula averages the hours worked on Monday and Tuesday (8.5 hours) and then computes its natural logarithm, approximately 2.20.

**Example 10: Using LN with MAX for Monthly Temperatures**

**Purpose of example:**To compute the natural logarithm of the highest temperature in a month.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | 1st Week Temp | 2nd Week Temp | Formula | Result |

2 | 25 | 28 | `=LN(MAX(A2:B2))` | 3.332205 |

**Explanation:**The formula finds the maximum temperature between the two weeks (28ยฐC) and computes its natural logarithm of approximately 3.33.

**Example 11: Using LN with MIN for Monthly Discounts**

**Purpose of example:**To compute the natural logarithm of the minor monthly Discount offered.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | 1st Discount | 2nd Discount | Formula | Result |

2 | 15 | 10 | `=LN(MIN(A2:B2))` | 2.302585 |

**Explanation:**The formula finds the minimum Discount between the two offers (10%) and computes its natural logarithm of approximately 2.30.

**Example 12: Using LN with COUNT for Number of Transactions**

**Purpose of example:**To compute the natural logarithm of the number of daily transactions.**Data sheet and formulas:**

A | B | C | D | |
---|---|---|---|---|

1 | Transaction 1 | Transaction 2 | Formula | Result |

2 | 120 | 150 | `=LN(COUNT(A2:B2))` | 0.693147 |

**Explanation:**The formula counts the number of transactions (2) and computes its natural logarithm, approximately 0.69.

### Part 3: Tips and tricks

- ๐ Remember that the LN function requires a positive actual number as its argument.
- ๐ The LN function can benefit financial and scientific calculations requiring natural logarithms.
- ๐ If you’re looking to compute the logarithm with a base other than ‘e’, consider using the LOG function in Excel.
- ๐ Always ensure that the number provided to the LN function is positive to avoid errors.