Kurtosis

The Kurtosis of a probability distribution indicates how much data resides in the tails.
Kurtosis is a measure of the combined weight of a distribution's tails relative to the middle of the distribution curve (the mean).
Distributions with a large kurtosis have more tail data than normally distributed data, which appears to bring the tails in toward the mean.
Distributions with low kurtosis have fewer tail data, which appears to push the tails of the bell curve away from the mean.
A high kurtosis of the return distribution curve implies that there have been a number of fluctuations in the past (positive or negative) away from the mean.

Excel Function

The KURT function returns a positive value if the distribution is relatively peaked compared with the normal distrobution
This function returns a negative value if the distribution is relatively flat.

Mesokurtic Distribution

normal

Platykurtic Distribution

less than normal

Leptokurtic Distribution

more than normal