Seems like I have reached a plateau – for about a week speed & number of errors stayed more or less the same. I have tried to use this new skill in my daily tasks but have again noticed that I am totally lacking skills in using punctuation and other special characters which makes using touch-typing not practical yet.
With this in mind I have started to search for a software that includes other characters besides letters in training sessions. It turned out that using non-legacy mode it is already possible with http://www.keybr.com, however as I understood, digits are still out of the scope of the regular lessons. Anyway I am continuing my training sessions, now including punctuation & capital letters. Because of that reported stats have dropped significantly (as you can see on the last bar of the chart), the actual results are worse than the chart shows though because non-legacy version of the http://www.keybr.com has different charts and I will be posting those later, what you see on the last bar was an attempt to type in some text from the news site.
So my actual typing speed now is ~14 wpm on average, including punctuation & stuff. However a good news is that now I can start using touch-typing to some extent, for example to write this post. That wasn’t very fast but at least I see the progress and really believe that in some weeks ahead I will be able to type like this at work.