Data - Cluster Observations
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You can have two types of input data: columns of raw data or a matrix of distances.

Typically, you would use raw data. Each row contains measurements on a single item or subject. You must have two or more numeric columns, with each column representing a different measurement. You must delete rows with missing data from the worksheet before using this procedure.

If you store an n x n distance matrix, where n is the number of observations, you can use this matrix as input data. The (i, j) entry in this matrix is the distance between observations i and j. If you use the distance matrix as input, statistics on the final partition are not available.