def calculate_max_capacity(data):
    """
    Calculate maximum capacity from given data.

    Args:
        data (list): List of tuples containing version, size, and other metrics.

    Returns:
        tuple: Version with maximum capacity.
    """
    max_capacity = 0
    max_version = None
    for item in data:
        if item[1] > max_capacity:
            max_capacity = item[1]
            max_version = item[0]
    return max_version, max_capacity

# Example usage:
data = [('v5_1768236144', 108217.11959687909, 721, 15009.3),
        ('v5_1768235312', 89435.63603047856, 734, 12184.7),
        ('v5_1768235983', 98379.19963352643, 987, 9967.5)]
print(calculate_max_capacity(data))