Number of ads (dashed) or articles containing the term machine in combination with either fiets (green) or rijwiel (blue), as percentage of all ads or articles containing either fiets or rijwiel, by decade. Years on the x-axis refer to the decade starting in that year, except 1990, which refers to 1990-1995. Data before 1870 omited because small numbers make it meaningless to calculate percentages. Source: Delpher, analysis: dirkmjk.nl