In the process of calculating the profit over the same period, if the profit in the base period is negative, should the profit over the same period be positive or negative?

In the process of calculating the profit over the same period, if the profit in the base period is negative, should the profit over the same period be positive or negative?

In this case, it can not be explained by the growth rate, but should be explained as follows:
"Last year, the company lost 100000 yuan. This year, under the fierce market competition, through the joint efforts of the company's colleagues, it turned losses into profits at one stroke and made a profit of 50000 yuan."

Growth rate = growth amount / number of base periods * 100% = (number of reporting periods - number of base periods) / number of base periods * 100%. If the data of base period is negative, how should it be expressed?
For example, a company suffered a loss of 190000 in 2006 and made a profit of 120000 in 2007?

It's not easy to calculate the rate, so we have to calculate the amount, an increase of 310000 yuan

How to calculate the growth rate of last year's negative number and this year's positive number

In addition to the previous year's base number, it may be divided by the absolute value of the previous year