Forecasting without extensions. (Not is trend line)

[walxiney_Planner]

Hello

Please somebody can help me? I need make a Forecasting like this... He doesn't show how to do... 

https://community.qlik.com/t5/New-to-Qlik-Sense/Qlik-Sense-line-chart-forecast-min-max/td-p/92089

But I can only make something like this... I don't want to show trend lines

I'm using this expression...

if(sum({<Ano={2019}>}Vendas),sum({<Ano={2019}>}Vendas)

,linest_m(total aggr(if(sum({<Ano={2019}>} Vendas), sum({<Ano={2019}>} Vendas), Mês), Mês))* only(Mês)

+linest_b(total aggr(if(sum({<Ano={2019}>} Vendas),sum({<Ano={2019}>}Vendas))), Mês))

and if I use the linest_m() and linest_b() without the aggr() and if() show the same result...

if(sum({<Ano={2019}>}Vendas),sum({<Ano={2019}>}Vendas),linest_m(Vendas,Mês)*mês + Linest_b(Venda,Mês),)

the dataset used is this

Dado:
Load *
Inline
[Mês, Ano, Vendas
01, 2018, 123.000,00
02, 2018, 147.000,00
03, 2018, 852.000,00
04, 2018, 357.000,00
05, 2018, 654.000,00
06, 2018, 951.000,00
07, 2018, 876.000,00
08, 2018, 684.000,00
09, 2018, 789.000,00
10, 2018, 125.000,00
11, 2018, 321.000,00
12, 2018, 159.000,00
01, 2019, 123.000,00
02, 2019, 147.000,00
03, 2019, 852.000,00
04, 2019, 357.000,00
05, 2019, 654.000,00
];

Thanks for your attention.

[walxiney_Planner]

Somebody have some idea?