C++ :: Size Of Process Grows Larger For Lots Of Small Memory Allocations

Why the size of a process grows larger in size for lots of small memory allocations. For example, say I have this struct, which is 16 bytes (for a 32 bit build):

Code:
struct Person {
int iID;
int iAge;
char * pForeName;
char * pSurName;
};

If I allocate memory like this:

Code:
LPBYTE lpB = new BYTE[sizeof(Person) * 1000000];

Then my process grows to 16,48KB in size, which is what I expected. However if I allocate memory like this:

Code:
Person * lpPerson;
for(int i = 0; i < 1000000; ++i)
lpPerson = new Person;

Then the process grows to 78,656KB, which I don't understand.

Additionally, I was surprised to find a vector acts more similarly to the first example. This code:

Code:
Person temp = { 0 };
std::vector<Person> people;
for(int i = 0; i < 1000000; ++i)
people.push_back(temp);

Only increases the process memory to 16,892.