How can one protect oneself from a dividend stock with decreasing price?
If by saying you wish to invest "for the long term 5-10 years" I take it you mean to hold a stock for between 5-10 years. If this is the case, this is the fundamental flaw in your screening algorithm. No company stock price continues to go up without end for 5-10 years. The price of every company's stock goes down at some point. You have to decide on a company by company basis whether you want to ride out the downturn or sell and get out. This is a personal decision based on your own research. The list of screening criteria you list indicates you are looking for solid earnings companies. Try not to apply these rules rigidly because every company runs through a rough patch. At times past, GE (for example) met all of your criteria. However, in 2017, it would not and therefore would not meet your screening criteria. Would you sell GE if you owned it? Maybe, or maybe you would hold through the downturn. The same be said for MSFT in 2010 or AAPL pre-Jobs return. A rule you may want to add to your list: know the company business well; that is, don't invest in companies you have no understanding of their business model.