Power Consumption STM32

Hello everyone,

I need to get some information about the power consumption of the STM32 Nucleo-64 with STM32F401RE MCU.
The board is powered from the computer's USB port.
I created a project in which the main while loop is empty, all peripherals are disabled and the HCLK frequency (from PLLCLK with HSI PLL source mux) is 84 MHz.

I used a USB Digital Tester J7-c (between the board and the pc's USB port) and I obtained this values:
5.04 V; 0.05 A; 0.29 W; 92 Ω.

Changing the HCLK frequency from 84 MHz to 42 MHz, I obtain this values:
5.04 V; 0.04 A; 0.25 W; 108 Ω.

But if I use the PCC (Power Consumption Calculator) tool with these step parameters (RUN mode, power scale: scale2, memory fetch type: flash, VDD: 3.3 V, voltage source: battery, CPU freq.: 84 MHz, all peripherals disabled) I get a step consumption of 20.2 mA (= 0.0202 A).
Instead, with these step parameters (RUN mode, power scale: scale3, memory fetch type: flash, VDD: 3.3 V, voltage source: battery, CPU freq.: 42 MHz, all peripherals disabled) I get a step consumption of 11.03 mA (= 0.01103 A).
I read from the datasheet that the MCU is placed under the conditions of TA=25°C and VDD=3.3 V. The USB provides 5V which is stepped-down to 3.3V for the MCU, right?

So, why did the USB tester give me that values?
Shouldn't I get a value close to 0.0202 A (with 84 MHz) and 0.01103 (with 42 MHz)?

Could anyone please help me?