The turnover (M HUF) of a company between 2017 and 2019 in the 3. quarters: 

Year Turnover of the 3. quarter 

2017 20 

2018 24 

2019 25 

The equation of the linear trend: ý=11+1•t (t=1;2;3...n) 

Seasonal variances 

Quarters (M HUF) I. II. III. IV. 

rough seasonal variances -3.0 -2.0 .... 4.0 

corrected seasonal variances 

Tasks: 

a.) Interpret the parameters! 

b.) Calculate and interpret the corrected seasonal variance in the 3. quarters! 

c.) Calculate and interpret the irregular component in 2019 of the third quarter! 

d.) Forecast the value in 2021 of the second quarter!