PGINVIT impairment of investments in subsidiaries and book value

I have difficulties in understanding the cash flow statement of PGINVIT.

1. The item “Impairment of investments in subsidiary” seems to be extremely high compared to last year. How do we know what led to this and in which subsidiary?

2. Do the numbers inside brackets like (11362.6) mean negative values?

3. In spite of the huge impairment, we still see the cash flow is positive and better than last year. Is my understanding correct that (45938.75) invested last year is an outflow of cash and this has given returns, a positive inflow of 11720.73 in 2023?

Also, I noticed that the book value is alternating between a high and low, like a square value. What could be the reason for this?