Conky - string formatting

I have conky the record: ${color lightblue} Down: ${downspeed wlan0} Up: ${upspeed wlan0} Conky prints link speed, but the text moves: Down: OB Up: OB Down: 60B Up: 60B Down: 148B Up: 148B Down: 1KiB Up: 1KiB Down: 1.8KiB Up: 1.8KiB Down: 1.08KiB Up: 1.08KiB Down: 31.8KiB Up: 31.8KiB Based on this topic https://unix.stackexchange.com/questions/57789/creating-conky-text-variables-with-zero-padding I tried to format the output, but the text still moves. ${color lightblue} Down: ${lua_parse format %7s ${downspeed wlan0}} Up: ${lua_parse format %7s ${upspeed wlan0}} I want the printed output conky: Down: 0B Up: 0B Down: 60B Up: 60B Down: 148B Up: 148B Down: 1KiB Up: 1KiB Down: 1.8KiB Up: 1.8KiB Down: 1.08KiB Up: 1.08KiB Down: 31.8KiB Up: 31.8KiB