ESXi datastore sizing question

I installed ESXi 6.7 on a system whose only storage is a 2TB SSD. I see that the datastore occupies all available space left over after the installation. I want the space occupied by the datastore to be much smaller and I want the leftover space simply to be unallocated instead of being dedicated to ESXi. How can I accomplish that? Here's the current partition information:

Thanks,

David Habermehl