Remove duplicate customer records
Intermediate Data AnalystCustomer exports often contain repeat records. Before you analyze revenue, import contacts, or send a campaign, you need a clear rule for which row stays and which rows should be removed.
In this exercise, the Customer ID should identify one customer. Some IDs appear more than once because the same customer was exported multiple times. Your rule is simple: keep the first row for each Customer ID, then mark any later rows with the same ID for removal.
This is a good fit for COUNTIF with an expanding range. The range starts at the first Customer ID and grows as you copy the formula down, so each row can check whether its ID has appeared before.
Your task:
Fill cells E2:E13 with formulas that return Keep for the first occurrence of each Customer ID and Remove for later repeats. Base your logic on the Customer ID column, not the customer name.
Need some help?
Hint 1
Use Customer ID as the identifier. A repeated name is not enough for this exercise unless the Customer ID repeats too.
Hint 2
COUNTIF can count how many times the current Customer ID appears in the rows seen so far.
Hint 3
Lock the start of the Customer ID range, but let the end of the range move as you fill down. A running count of 1 means Keep; anything higher means Remove.
Remove duplicate customer records
Intermediate Data AnalystCustomer exports often contain repeat records. Before you analyze revenue, import contacts, or send a campaign, you need a clear rule for which row stays and which rows should be removed.
In this exercise, the Customer ID should identify one customer. Some IDs appear more than once because the same customer was exported multiple times. Your rule is simple: keep the first row for each Customer ID, then mark any later rows with the same ID for removal.
This is a good fit for COUNTIF with an expanding range. The range starts at the first Customer ID and grows as you copy the formula down, so each row can check whether its ID has appeared before.
Your task:
Fill cells E2:E13 with formulas that return Keep for the first occurrence of each Customer ID and Remove for later repeats. Base your logic on the Customer ID column, not the customer name.
Need some help?
Hint 1
Use Customer ID as the identifier. A repeated name is not enough for this exercise unless the Customer ID repeats too.
Hint 2
COUNTIF can count how many times the current Customer ID appears in the rows seen so far.
Hint 3
Lock the start of the Customer ID range, but let the end of the range move as you fill down. A running count of 1 means Keep; anything higher means Remove.