Although we also place links on 3 monthly, 6 monthly and yearly basis but we generally and most usually follow the per month placement option. Below is a little overview of what benefits can a text link bring on monthly basis rather than any longer period.
Per month placement option means a text link we place on any site will be paid for the entire month and there is no guarantee that the link will stay even a single day above a month. However, the minimum period where the link will stay on the site is generally four months with renewal on each month (1st of each month). The option is pretty flexible for advertiser and web owners simultaneously as if any link placed on any site is failed to generate the minimum expected results for the advertiser, the advertiser can drop the deal on the preceding month. In the other side, if the link itself presents any conflict or drops some SEO stats of the link hosted site, the web owner is free to pull the link down by the end of that month.
One more benefit for web owners is to get a higher revenue comparing to one on 3, 6 or 12 month placements. Similarly the advertiser can make a slices of small installments whereas can keep the link for period as longer as he wish.
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